Question

quiz m: proportions and scale factors (11/26)
julo considers the reduction of the triangle.
not drawn to scale
what is the correct cross product that he should use to solve for the missing dimension?
hint: set up the proportion first, then find the cross product.
(8)(12) = 21x
(8)(21) = 12x
(12)(8) = 12x
(12)(21) = 8x

Explanation:

Step1: Set up the proportion

Since the triangles are similar (reduction), the ratios of corresponding sides are equal. So, $\frac{12}{8}=\frac{21}{x}$.

Step2: Cross - multiply

Cross - multiplying the proportion $\frac{12}{8}=\frac{21}{x}$ gives $(8)(21)=12x$.

Answer:

(8)(21) = 12x (the second option: (8)(21) = 12x)