Please check answers)
posted by Hannah on .
Perform the indicated operations and simplify the result. Leave your answer in factored form.
1) x/16  1/x all over 1 + 4/x
A) x+4/16
B) x4/16
C) 16/x+4
D) 16/x4
E) 16/x+4
I chose answer C. I saw this as x^216/ x+4.
Multiply the following using the FOIL method. Express your answer as a single polynomial in standard form.
2) (sqrt a + a)(sqrt a  a)
A) a  a^2
B) a + a^2
C) sqrt a  a^2
D) 2 sqrt a
E) a
I chose answer C.
Simplify the expression. Express answers so that all exponents are positive. Whenever an exponent is 0 or negative, we assume that the base is not 0.
( 8 x^1 / 3 y^1)^2
A) 9 y^2 / 64 x^2
B) 64 x^2 / 9 y^2
C) 64 y^2 / 9 x^2
D) 9 x^2 / 64 y^2
E) 9 x^2 /64 y^2
I chose answer A) 9 y^2 / 64 x^2

1. first multiply both top and bottom of your fraction by 16x/(16x) to get
(x^2  16)/(16x64)
= (x+4)(x4)/(16(x4))
= (x+4)/16 which is probably what you meant when you typed a)
2. (√a + a)(√a  a) = a  a^2 , which is b)
3. ( 8 x^1 / 3 y^1)^2
= [(8/x) / (3/y)]^2
= [(8/x)(y/3)]^2
= [(8y)/(3x)]^2
= [(3x)/(8y)]^2
= 9x^2/(64y^2) or D) 
SO for #2 the answer is aa^2 or +a^2?