Find the value of ‘x’ so that.

The two given angles are (2x + 15)° and (3x-10)°.

We know that vertically opposite angles are equal.

The angle which is vertically opposite to (2x + 15)° is also

corresponding to (3x-10)°.

For l ∥ m, the corresponding angles must be equal.

∴ (2x + 15)° and (3x-10)° are both equal to the same angle.

According to the given condition,

(2x + 15)° = (3x-10)°

⇒ 2x + 15 = 3x – 10

⇒ 2x – 3x = -10 – 15 (Transposing 3x to LHS and 15 to

RHS)

-x = -25

∴ x = 25 (Multiplying by -1 throughout)

∴ The value of x so that l ∥ m is 25°.