Answer:
x = ± 13
Step-by-step explanation:
Given
x² = 169 ( take the square root of both sides )
x = ±
= ± 13
Since 13 × 13 = 169 and - 13× - 13 = 169
Answer:
Step-by-step explanation:
1.

c+9=±8
either c=8-9=-1
c=-8-9=-17
so c=-1,-17
D
2.
8x^2-3=2
8x^2=5


so A
3.

so D
or
By the isosceles triangle theorem the two angles opposite the equal sides are themselves equal while if the third side is different then the third angle is different.
A+(-1.3)=-4.5
Add 1.3 to both sides of the equation
a=-3.2