Which equation is the inverse of y = 9x2 – 4?
y = StartFraction plus-or-minus StartRoot x + 4 EndRoot Over 9 EndFraction
y = plus-or-minus StartRoot StartFraction x Over 9 EndFraction + 4 EndRoot
y = StartFraction plus-or-minus StartRoot x + 4 EndRoot Over 3 EndFraction
y = StartFraction plus-or-minus StartRoot x EndRoot Over 3 EndFraction + two-thirds

The inverse is ±sqrt((x+4)/9)

Step-by-step explanation:

y = 9x^2 – 4

We want to find the inverse

Exchange x and y

x = 9y^2 -4

Solve for y

Add 4 to each side

x+4 = 9y^2 -4+4

x+4 = 9y^2

Divide each side by 9

(x+4)/9 = 9/9y^2

(x+4)/9 = y^2

Take the square root of each side

±sqrt((x+4)/9) = sqrt(y^2)

±sqrt((x+4)/9) = y

The inverse is ±sqrt((x+4)/9)

y = StartFraction plus-or-minus StartRoot x + 4 EndRoot Over 3 EndFraction

Step-by-step explanation:

y = 9x² - 4

Make x the subject

9x² = y + 4

x² = (y + 4)/9

x = +/- sqrt(y + 4)/sqrt(9)

x = +/- sqrt(y + 4)/3

Interswitch variables

inverse = +/- sqrt(x + 4)/3

4 and 5)16.97 or 12√2

6)15.59 or 9√3

7)y = 15.59 or 9√3     x =27

8)17.80