SOLUTION: Please will someone help me with these? I appreciate it. solve: 8x + 9 = 25 4x + 10 = 30 Solve using the principles together -8x - 24 = -29 1/3 3x + 10x + 91 3x - 18

Algebra ->  Equations -> SOLUTION: Please will someone help me with these? I appreciate it. solve: 8x + 9 = 25 4x + 10 = 30 Solve using the principles together -8x - 24 = -29 1/3 3x + 10x + 91 3x - 18      Log On


   

Question 132934: Please will someone help me with these? I appreciate it.
solve:
8x + 9 = 25
4x + 10 = 30
Solve using the principles together
-8x - 24 = -29 1/3
3x + 10x + 91
3x - 18 = 9
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
As long as you do the exact same thing to both
sides of an equation, the equation is still true
8x + 9 = 25
4x + 10 = 30
Solve using the principles together
-8x - 24 = -29 1/3
3x + 10x + 91
3x - 18 = 9
-----------------
8x+%2B+9+=+25
Subtract 9 from both sides
8x+=+25+-+9
8x+=+16
Divide both sides by 8
x+=+2 answer
----------------
4x+%2B+10+=+30
Subtract 10 from both sides
4x+=+30+-+10
4x+=+20
Divide both sides by 4
x+=+5 answer
----------------
-8x+-+24+=+-29+1%2F3
First, what is 29 1/3? How many 1/3's are there in 29?
The answer is 3%2A29+=+87 1/3's. Add 87 1/3's and
1/3 to get 88 1/3's. So, the equation becomes
-8x+-24+=+-%2888%2F3%29
Now multiply both sides by -1
8x+%2B+24+=+88%2F3
Multiply both sides by 3
24x+%2B+72+=+88
Subtract 72 from both sides
24x+=+16
Divide both sides by 24
x+=+16%2F24
Now multiply the right side by %281%2F8%29+%2F+%281%2F8%29 which is
actually 1 and multiplying by 1 does not change
anything
x+=+%28%281%2F8%29%2A%2816%29%29+%2F+%28%281%2F8%29%2A%2824%29%29
x+=+2%2F3 answer
check the answer:
-8x+-+24+=+-29+1%2F3
-8%2A%282%2F3%29+-+24+=+-29+1%2F3
-%2816%2F3%29+-+24+=+-%2888%2F3%29
16%2F3+%2B+24+=+88%2F3
multiply both sides by 3
16+%2B+72+=+88
88+=+88
You can, and should check all of your answers like this,
unless you don't have time, like during a test.
That's all I have time for, good luck.