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

3

step-by-step explanation:

in standard form:

a= dictionaries

b= maps

you have to buy 3 dictionaries, so put a 3 next to the a (dictionaries) so that you can multiply them by each other.

a3+b= 60 (the amount of money you have)

we already know the cost of a=15 so replace a with $15

($15 x 3)+b=60

multiply 15 and 3 to get $45 and replace it with $45

45+b=60

and then replace b with 15 to get the total:

45+15=60

that means you have $15 left after buying 3 dictionaries.

15 divided by the cost of a map ($5) equals 3.

so you can buy 3 maps.

sorry if it was confusing!

a

step-by-step explanation: