Use substitution to write an equivalent quadratic equation. (3x + 2)2 + 7(3x + 2) - 8 = 0
DONE

  z^2 +7z -8 = 0

Step-by-step explanation:

Let z = 3x+2. Then we can substitute z wherever we see 3x+2.

  z^2 +7z -8 = 0 . . . . equivalent quadratic

__

This is easily factored to ...

  (z -1)(z +8) = 0

So, the original quadratic has solutions ...

  (3x +2) -1 = 0

  x = -1/3

and

  (3x +2) +8 = 0

  x = -10/3

m∠cdf = 43° , m∠gdf = 114°, m∠gde = 23°, m∠edh = 23° , m∠cdh = 157°

step-by-step explanation:

since, it is given that de bisects the angle gdh ⇒ de divides the angle gdh into two equal angles.

⇒ m∠gde = m∠edh

⇒ 8·x   - 1 = 6·x + 5

⇒ x = 3

so, m∠gde = 8·x - 1 = 23°

and m∠edh = 23°

now, it is given ∠cde is an straight angle so, m∠cde = 180°

⇒ m∠cdf + m∠fdg + m∠gde = 180°

⇒ 43° + m∠fdg + 23° = 180°

⇒ m∠fdg = 114°

again, m∠cde = m∠cdh + m∠edh = 180°

m∠cdh + 23° = 180°

⇒ m∠cdh = 157°

the first option i believe

step-by-step explanation: