Answer:
Given:
, y =6
To prove: x =7
On substituting the value of y =6 in the equation 7y = 8x -14 to solve for x.
or
42 = 8x -14 ......[1]
Addition Property of equality states that you add the same number to both sides of an equation.
Add 14 to both sides in equation [1];
42+14 =8x -14+14
Simplify:
56 = 8x
or
8x =56 ......[2]
Division Property of equality states that you divide the same number to both sides of an equation.
Divide by 8 to both sides of an equation [2];

Simplify:
x =7 Hence proved!
A two Column proof:
Statement Reason
1. 7y = 8x -14 Given
y= 6
2. 7(6) = 8x -14 Substitution property
3. 42+14 = 8x Addition property of equality
4. 56 =8x Simplify
5. x =7 Division Property of equality
It is 10x the value of the one in the thousands place
I'll just help quickly with a couple of expressions that are equivalent.
3(m+5+9m)
If you solve it out, you get 3m+15+27m.
Simply the expression to get 30m+15.
You can regroup to make another expression 5(6m+3) which is also equal.
10% of 120 = 12
12 x 7 = 84
70% = 84
120 x 70 = 8400
8400 / 100 = 84
It’s either showing you that both sides of the equation equal to the same thing or that you can find 70% of 120 by using the steps on the right