Question

△ABC and △DEF are similar triangles. Find BC.

Answer 1

5 units

Explanation:

We know that Triangles ABC and DEF are similar, therefore their values will be Equal

So , x + 7 + x - 4 = 12 + 5

2x + 3 = 15
2x = 15-3
2x = 12
x = 6

So in Triangle ABC , AC = x + 7 = 6 + 7 = 13
Therefore, by Pythagorean Therom,

BC^2 + AB^2 = AC^2

BC^2 + 144 = 169

BC^2 = 169 -144 = 25

BC =
`√(25) = 5`

Hope it helps.