Question

The two triangles

Answer 1

Solution:

Note that:

• (3x)/20 = (4x + 2)/28

Using cross multiplication:

• (3x)/20 = (4x + 2)/28
• => (3x) × 28 = (4x + 2) × 20

Simplifying both sides:

• => 84x = 80x + 40

Subtracting 80x both sides:

• 84x = 80x + 40
• => 84x - 80x = 80x + 40 - 80x

Simplify the LHS:

• => 84x - 80x = 40
• => 4x = 40
• => x = 10

Answer 2

Ratio remains same

$\\ \rm\bull\rightarrowtail \dfrac{20}{3x}=\dfrac{28}{4x+2}$

$\\ \rm\bull\rightarrowtail 84x=20(4x+2)$

$\\ \rm\bull\rightarrowtail 84x=80x+40$

$\\ \rm\bull\rightarrowtail 4x=40$

$\\ \rm\bull\rightarrowtail x=10$