Question

In the function y = |x² - 4|, for
how many values of x does y = 3?

Answer 1

4 answers

Explanation:

y = |x² - 4|

3 = |x² - 4|

3 = x² - 4 and -3 = x² - 4

3+4=x² - 4 + 4 and -3+4=x² - 4 + 4

7=x² and 1=x²

x=
`√(7)` and x=-
`√(7)` since x²=7

x=-1 and x=1 since x²=1

x= -
`√(7)`,
`√(7)`, -1, 1 ==> 4 answers