Stuck on triangle geometry problem
$begingroup$
The answer is $378$ but I can't seem to get it. I know that the triangles are similar, but I can't get past that. Any help is appreciated! Thanks!
geometry
edited Jan 2 at 20:44
amWhy
1
asked Jul 5 '14 at 1:10
Helpappreciated111Helpappreciated111
185
$endgroup$
add a comment |
$begingroup$
The answer is $378$ but I can't seem to get it. I know that the triangles are similar, but I can't get past that. Any help is appreciated! Thanks!
geometry
edited Jan 2 at 20:44
amWhy
1
asked Jul 5 '14 at 1:10
Helpappreciated111Helpappreciated111
185
$endgroup$
add a comment |
$begingroup$
The answer is $378$ but I can't seem to get it. I know that the triangles are similar, but I can't get past that. Any help is appreciated! Thanks!
geometry
edited Jan 2 at 20:44
amWhy
1
asked Jul 5 '14 at 1:10
Helpappreciated111Helpappreciated111
185
$endgroup$
The answer is $378$ but I can't seem to get it. I know that the triangles are similar, but I can't get past that. Any help is appreciated! Thanks!
geometry
geometry
edited Jan 2 at 20:44
amWhy
1
asked Jul 5 '14 at 1:10
Helpappreciated111Helpappreciated111
185
edited Jan 2 at 20:44
amWhy
1
asked Jul 5 '14 at 1:10
Helpappreciated111Helpappreciated111
185
edited Jan 2 at 20:44
amWhy
1
edited Jan 2 at 20:44
amWhy
1
edited Jan 2 at 20:44
amWhy
1
1
asked Jul 5 '14 at 1:10
Helpappreciated111Helpappreciated111
185
asked Jul 5 '14 at 1:10
Helpappreciated111Helpappreciated111
185
asked Jul 5 '14 at 1:10
Helpappreciated111Helpappreciated111
185
185
add a comment |
add a comment |
2 Answers
2
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$begingroup$
Hint: Lengths are scaled by a factor of $3$. So area is scaled by a factor of ???
answered Jul 5 '14 at 1:13
André NicolasAndré Nicolas
454k36429816
$endgroup$
add a comment |
$begingroup$
Since $AB=BC=CD$, $AD=3times CD$. Because the triangles are similar, every side must be $3$ times as big. The area of the upper triangle is $42 = frac{CEtimes ED}{2}$, the area of the bigger triangle is given by $A = frac{3CE times 3ED}{2}$, or $9$ times that of the smaller triangle, so $A = 378$
answered Jul 5 '14 at 1:16
scrblnrd3scrblnrd3
345211
$endgroup$
add a comment |
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2 Answers
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2 Answers
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active
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$begingroup$
Hint: Lengths are scaled by a factor of $3$. So area is scaled by a factor of ???
answered Jul 5 '14 at 1:13
André NicolasAndré Nicolas
454k36429816
$endgroup$
add a comment |
$begingroup$
Hint: Lengths are scaled by a factor of $3$. So area is scaled by a factor of ???
answered Jul 5 '14 at 1:13
André NicolasAndré Nicolas
454k36429816
$endgroup$
add a comment |
$begingroup$
Hint: Lengths are scaled by a factor of $3$. So area is scaled by a factor of ???
answered Jul 5 '14 at 1:13
André NicolasAndré Nicolas
454k36429816
$endgroup$
Hint: Lengths are scaled by a factor of $3$. So area is scaled by a factor of ???
answered Jul 5 '14 at 1:13
André NicolasAndré Nicolas
454k36429816
answered Jul 5 '14 at 1:13
André NicolasAndré Nicolas
454k36429816
answered Jul 5 '14 at 1:13
André NicolasAndré Nicolas
454k36429816
answered Jul 5 '14 at 1:13
André NicolasAndré Nicolas
454k36429816
454k36429816
add a comment |
add a comment |
$begingroup$
Since $AB=BC=CD$, $AD=3times CD$. Because the triangles are similar, every side must be $3$ times as big. The area of the upper triangle is $42 = frac{CEtimes ED}{2}$, the area of the bigger triangle is given by $A = frac{3CE times 3ED}{2}$, or $9$ times that of the smaller triangle, so $A = 378$
answered Jul 5 '14 at 1:16
scrblnrd3scrblnrd3
345211
$endgroup$
add a comment |
$begingroup$
Since $AB=BC=CD$, $AD=3times CD$. Because the triangles are similar, every side must be $3$ times as big. The area of the upper triangle is $42 = frac{CEtimes ED}{2}$, the area of the bigger triangle is given by $A = frac{3CE times 3ED}{2}$, or $9$ times that of the smaller triangle, so $A = 378$
answered Jul 5 '14 at 1:16
scrblnrd3scrblnrd3
345211
$endgroup$
add a comment |
$begingroup$
Since $AB=BC=CD$, $AD=3times CD$. Because the triangles are similar, every side must be $3$ times as big. The area of the upper triangle is $42 = frac{CEtimes ED}{2}$, the area of the bigger triangle is given by $A = frac{3CE times 3ED}{2}$, or $9$ times that of the smaller triangle, so $A = 378$
answered Jul 5 '14 at 1:16
scrblnrd3scrblnrd3
345211
$endgroup$
Since $AB=BC=CD$, $AD=3times CD$. Because the triangles are similar, every side must be $3$ times as big. The area of the upper triangle is $42 = frac{CEtimes ED}{2}$, the area of the bigger triangle is given by $A = frac{3CE times 3ED}{2}$, or $9$ times that of the smaller triangle, so $A = 378$
answered Jul 5 '14 at 1:16
scrblnrd3scrblnrd3
345211
answered Jul 5 '14 at 1:16
scrblnrd3scrblnrd3
345211
answered Jul 5 '14 at 1:16
scrblnrd3scrblnrd3
345211
answered Jul 5 '14 at 1:16
scrblnrd3scrblnrd3
345211
345211
add a comment |
add a comment |
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