Algebra 1 Answer Evaluation (Reiny)
posted by Anonymous on .
Evaluate each expression for the given value(s) of the variable(s).
1. t^6 for t = 2
A: 1/64
2. r^0s^2 for r = 8 and s = 10
A: 1/100?
Simplify.
3. x^4/x^6
A: 1/x^4y^6? Or x^4y^6?
4. a^3/b^2
A: 1/a^3b^2? Or a^3b^2?
5. The lead in a mechanical pencil has a diameter of 0.5 mn. Write this number in scientific notation.
A: ?
Simplify.
6. 3^5 x 3^3
A: 3^2
7. a^3 x a^6 x a^2
A: a^15
8. (3x^4)^3
A: 27x^12
9. (4d^7)^2
A: 16d^14

#1. Nope 2^6 = 64 (2*2*2*2*2*2)
2^6 = 1/2^6 = 1/64
#2 ok
#3 where did the y's come from? When dividing, subtract exponents
x^4/x^6 = x^(4(6)) = x^10
#4 negative exponents indicate reciprocals. As a shortcut, they mean the item switches top and bottom in a fraction
a^3/b^2 = b^2/a^3
#5 0.5 = 5.0x10^1
#6 ok
#7 nope. add the exponents when multiplying
a^(362) = a^5
#8 ok
#9 nope.
(4)^2 = (4)(4) = +16
4^2 = (4^2) = 16
powers are done before subtraction unless parentheses change the order. 
1. 2^4 = 64 , not 1/64
2. ok
3. x^4 y^6 , your first choice is incorrect
4. a^3/b^2 = a^(3 (2)) = a^1 or 1/a
5. 0.5 = 5.0 x 10^1
6. 3^2 = 9 , they probably want the actual answer
7. a^3 x a^6 x a^2 = a^5 or 1/a^5 , notice 362=5
8. ok
9. (4d^7)^2 = +16 d^14
looks like some further review is needed. 
I am confused. Both of you has written different answers to many of the questions I have answered incorrectly. Which is correct?

I messed up in #3 and #4
#3, I looked at your answer and saw the y's, should have looked at the original question which had no y values.
answer is x^10 , see Steve's
#4.
a^3/b^2 = b^2/a^3, see Steve's
We have the same answers for the rest