Question

Use the quadratic formula s to solve 2y^2-6y-8=0


{-4,-1}

{4,-1}

{-4,1}

{4,1}

Answer 1

Answer:

{4, - 1}

Step-by-step explanation:

Given

2y² - 6y - 8 = 0 ← in standard form

with a = 2, b = - 6, c = - 8

Using the quadratic formula to solve for y

y = ( - (- 6) ± $\sqrt{(-6)^2-(4(2)(-8)}$ ) / (2 × 2)

  = ( 6 ± $\sqrt{36+64}$ ) / 4

  = ( 6 ± $\sqrt{100}$ ) / 4

  = ( 6 ± 10 ) / 4

x = $\frac{6+10}{4}$ = $\frac{16}{4}$ = 4

OR

x = $\frac{6-10}{4}$ = $\frac{-4}{4}$ = - 1

Solution is { 4, - 1 }