Answer:
x = 770
Explanation:
You want the solution to the equation 6(915 - x) = 100 + x.
Solution
It often works well to simplify the equation first. Here, that means eliminating parentheses using the distributive property:
6(915) -6(x) = 100 +x
5490 -6x = 100 +x . . . . . . . . carry out the multiplication
5490 -6x +6x = 100 +x +6x . . . . . add 6x to both sides
5490 = 100 +7x . . . . . . . . . . collect terms
5490 -100 = 100 +7x -100 . . . . . . subtract 100 from both sides
5390 = 7x . . . . . . . . . . . . . . collect terms
5390/7 = (7x)/7 . . . . . . . . . . . . . . . . divide both sides by 7
770 = x . . . . . . . . . . . . . . . . carry out the division
The solution to the equation is x = 770.
__
Check
6(915 -770) = 100 +770 . . . . use the value of x in the equation
6(145) = 870 . . . . true
__
Additional comment
After eliminating parentheses, this is a 3-step linear equation, so is solved in the usual way. First, the variable terms are collected on one side of the equal sign. Then the constant terms are collected on the other side of the equal sign. Finally, the equation is divided by the coefficient of the variable.