Answer: x=7
ab=21
bc=14
Step-by-step explanation:
ab=3x
bc=2x±7
ac=42
3x±2x±7=42
5x±7=42
5x=42-7
5x=35
to get the value of x you divide 35 by 5x
35÷5x=7
so the value of x is 7
ab=3x
x=7
3x=7×3x
7×3=21
x=7
2x=7×2x
2×7=14
I'll do the first two to get you started
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Problem 1
A = 3 = starting value
B = 10 = ending value
C = percent change
C = [ (B - A)/A ] * 100%
C = [ (10-3)/3 ] * 100%
C = (7/3) * 100%
C = 2.3333333 * 100%
C = 233.33333%
C = 233.3%
The positive C value means we have a percent increase. If C was negative, then we'd have a percent decrease.
<h3>Answer: 233.3% increase</h3>
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Problem 2
A = 9 = start value
B = 20 = end value
C = percent change
C = [ (B - A)/A ] * 100%
C = [ (20-9)/9 ] * 100%
C = (11/9)*100%
C = 1.2222222222*100%
C = 122.22222222%
C = 122.2%
<h3>Answer: 122.2% increase</h3>
4(x+7)=8x-20
4x+28=8x-20
28=4x-20
48=4x
x=12
If you would like to solve the equation -5x - 25 = 78, you should do this using the following steps:
<span>-5x - 25 = 78
</span>-5x - 25 + 25 = 78 + 25
-5x + 0 = 103
-5x = 103 /(-5)
x = 103 / (-5)
x = - 103/5 = - 20.6
The error was already made at step 1.
1:4 and 6:24 because 3/3=1 and 12/3=4 and 6/2=3 and 24/2=12
