2006-12-11 06:25:20 · 15 answers · asked by Danielle R 1 in Science & Mathematics ➔ Mathematics
Distributive property:
3x-2x+10=7
Combine like terms:
x+10=7
Subtract 10 on both sides:
x=-3
Check:
3(-3)-2(-3-5)=7
-9-2(-8)=7
-9+16=7
7=7
2006-12-11 06:45:28 · answer #1 · answered by Anonymous · 4⤊ 1⤋
3x - 2(x - 5) = 7
3x - 2x + 10 = 7
x + 10 = 7 (Subtract 10 from both sides)
x = -3
Check:
3(-3) - 2((-3) - 5) = 7
-9 - 2(-8) = 7
-9 + 16 = 7
7 = 7
QED
2006-12-11 09:35:40 · answer #2 · answered by CSUFGrad2006 5 · 3⤊ 0⤋
3x - 2(x - 5) = 7
3x - 2x + 10 = 7
x + 10 = 7
x + 10 - 10 = 7 - 10
x = - 3
The answer is x = - 3
Insert the x value into the equation
- - - - - - - - - - - - - - - - - - - - - - -
Check
3x - 2(x - 5) = 7
3( - 3) - 2(- 3 - 5) = 7
- 9 - 2 (-8) = 7
- 9 + 16 = 7
7 = 7
- - - - - - -s-
2006-12-11 06:43:01 · answer #3 · answered by SAMUEL D 7 · 2⤊ 1⤋
You have to know your order of operations. PEMDAS will help you remember it. It stands for:
Parentheses
Exponents
Multiplication
Division
Addition
Subtraction
So you do the operations in that order. In your equation you cannot simplify what is inside of the parentheses any more. So now you look for exponents, there aren't any so we go to the next step, multiplication. We have to get rid of the parantheses by multiplying:
3X-2(X-5)=7 ------> 3X-2X+10=7
Now you want to get x's on one side and the integers on the other, and simplify:
3X-2X+10=7 -------> 3X-2X= -3 ------> 1x = -3, or x= -3
-10 -10
2006-12-11 06:36:30 · answer #4 · answered by redrunner 2 · 2⤊ 1⤋
x = -3
2006-12-11 06:41:08 · answer #5 · answered by allsmilesinkc 1 · 2⤊ 0⤋
use foil for 3x-2(x - 5)
first 3x * x = 3x^2
outside 3x * -5 = -15x
inside -2(x) = -2x
last -2 * -5 = 10
combine like terms -15x -2x = -13x
3x^2 - 13x + 10 = 7 set to = 0
3x^2 -13x + 3 = 0 multiply through by -1
-3x^2 + 13x - 3 = 0
use quadratic equation when ax^2 + 13x + c = 0
x = -b + or - sqr(b^2 - 4ac)/2a
x will have 2 values because of + or - plug in the variables and solve for x and remember to Please Excuse My Dear Aunt Sally
2006-12-11 07:25:34 · answer #6 · answered by ikeman32 6 · 0⤊ 3⤋
x = -3
2006-12-11 06:29:10 · answer #7 · answered by Anonymous · 3⤊ 1⤋
3x - 2x +10 = 7
x+3
x = -3 is the final answer
2006-12-11 06:27:04 · answer #8 · answered by rod_dollente 5 · 3⤊ 1⤋
3x-2x+10=7
x+10=7
x=-3
2006-12-11 06:27:11 · answer #9 · answered by Anonymous · 3⤊ 1⤋
An equation.
X=-3
2006-12-11 06:27:03 · answer #10 · answered by DiphallusTyranus 3 · 3⤊ 1⤋