Question
The measures of two complementary angles are (2x – 7)° and (x + 4)°. Find x.
✓
Answer
We know that, sum of two complementary angles = 90°
∴(2x – 7) + (x + 4) = 90°
2x - 7 + x + 4 = 90°
⇒ 2x + x – 7 + 4 = 90°
⇒ 3x – 3 = 90°
⇒ 3x = 90 + 3
⇒ 3x = 93
$\Rightarrow x=\frac{93}{3}$
x = 31
∴(2x – 7) + (x + 4) = 90°
2x - 7 + x + 4 = 90°
⇒ 2x + x – 7 + 4 = 90°
⇒ 3x – 3 = 90°
⇒ 3x = 90 + 3
⇒ 3x = 93
$\Rightarrow x=\frac{93}{3}$
x = 31
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