Question

Find the missing angle

Answer 1

Answer:

$(4x - 15) + (3x + 6)+2x \\ = 90$

Open brackets

$4x - 15 + 3x + 6 + 2x = 90$

Simplify

$7x - 9 + 2x = 90$

$9x - 9 = 90$

$9x = 90 + 9$

$9x = 99$

$x = \frac{99}{9}$

$x = 11$

$4x - 15 \\ = 4 \times 11 - 15 \\ = 44 - 15 \\ = 29$

$3x + 6 \\ = 3 \times 11 + 6 \\ = 33 + 6 \\ = 39$

$2x \\ = 2 \times 11 \\ = 22$

Therefore,

$22 + 29 + 39 = 90$