Answer:
A. 45%
Step-by-step explanation:
34/75=45 = 45%
9514 1404 393
Answer:
1e. 2t² +8t -6
2h. a² +2ab -3b²
3b. 8r +4
4b. 6x +4y -11
5b. e -3
Step-by-step explanation:
1e. Combine like terms.
(3t² +3t -6) +(-t² +5t) = t²(3 -1) +t(3 +5) -6
= 2t² +8t -6
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2h. (2a² +3ab -4b²) -(a² +ab -b²)
Use the distributive property to eliminate parentheses. Note that all signs change in the second set of parentheses.
= 2a² +3ab -4b² -a² -ab +b² = a²(2 -1) +ab(3 -1) +b²(-4+1)
= a² +2ab -3b²
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3b. The hash marks indicate sides of the same length. The perimeter is the sum of all side lengths.
P = (4r -2) +2(2r +3)
P = 4r -2 +4r +6 . . . . . . eliminate parentheses
P = 8r +4 . . . . . . . . . . . . combine like terms
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4b. (3x +4y) +(5x -8) -(2x +3)
Note that the distributive property changes the sign of all terms in the last parentheses.
= 3x +4y +5x -8 -2x -3 . . . . eliminate parentheses
= x(3+5-2) +y(4) +(-8-3) . . . group like terms
= 6x +4y -11
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5b.
Bill's age - Erin's age = (2e-3) -(e) = e -3
The difference in their ages is (e -3).
4 x^2 + 20 x + 25 = 7
Divide both sides by 4:
x^2 + 5 x + 25/4 = 7/4
Write the left-hand side as a square:
(x + 5/2)^2 = 7/4
Take the square root of both sides:
x + 5/2 = sqrt(7)/2 or x + 5/2 = -sqrt(7)/2
Subtract 5/2 from both sides:
x = sqrt(7)/2 - 5/2 or x + 5/2 = -sqrt(7)/2
Subtract 5/2 from both sides:
Answer: x = sqrt(7)/2 - 5/2 or x = -5/2 - sqrt(7)/2
Answer:
N = -1/2
Step-by-step explanation:
We are adding in this, so we need to do the opposite to both sides, to get N by itself.
N + 3/4 - 3/4 = 1/4 - 3/4
N = -2/4 or, simplified, -1/2
8a - 4 = 25 + 6 (a - 8)
(distribute the 6)
8a - 4 = 25 + 6a - 48
(combine like terms 25 - 48)
8a - 4 = 6a - 23
( subtract 6a from both sides)
2a - 4 = -23
(add 4 to both sides)
2a = -19
(divide both sides by 2)
a = - 9.5
////CHECK/////
8 (-9.5) - 4 = 25 + 6 ( -9.5 -8)
(plug each side into a calculator)
-80 = -80
FINAL ANSWER:
a = -9.5
