Can someone solve these 1.) 4 + c =6 2.) x -7 =13
3.) 7c = 21
4.) x/5 = 9
Please and thanks u :)

1. evaluate 8x(2)y9(-2) for x=-1 and y=2 2. simplify the equation. -() 3. simplify the expression. [tex]\frac{5}{x(-2) y9(5)}[/tex]

Factor and solve to find roots x squared -x - 90 =0

What is the 8th term of the geometric sequence with this explicit formula? an= )(n-1)