x^2 - 81 = 0
a) -square root 9 , square root 9
b) -81 , 81
c) -9 , 9 ~~ MY ANSWER ~~
d) no real solutions
one more:
3x^2 - 147 = 0
a) -47, 49
b) -7, 7 ~~MY ANSWER~~
c) -square root 7 , square root 7
both look ok.
Okay, Thanks!
To solve the equation x^2 - 81 = 0, we need to find the values of x that make the equation true.
First, we can rearrange the equation to isolate the x^2 term:
x^2 = 81
Next, to find the values of x, we can take the square root of both sides of the equation:
√(x^2) = √81
Simplifying further:
|x| = 9
Here, the absolute value of x is equal to 9. This means that x can be either positive or negative 9. Therefore, the correct answer is c) -9 , 9.