Question

PLZ HELP SCALE FACTOR TRIANGLE A. 10.5 cm B. 31.5 cm C. 63 cm D. 189 cm

Answer 1

If two similar triangles have sides in the ratio a : b, then their areas are in the ratio a² : b².

We have the ratio:

$54:18=\dfrac{54}{18}=3:1$

Area of the smaler triangle = x

Area of the larger triangle = 567 cm²

Therefore we have the equation:

$567:x=3^2:1^2\\\\\dfrac{567}{x}=\dfrac{9}{1}\qquad|\text{cross multiply}\\\\9x=567\qquad|\text{divide both sides by 9}\\\\x=63$

Answer: C. 63 cm²