Solve 5x + 7 = 4x + 9
Linear equation, worked out line by line the way a teacher would write it.
Answer
| Solution | x = 2 |
Step-by-step solution
4 steps-
1 Given5 x + 7 = 4 x + 9
Solve for x.
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2 Subtract 4x from both sides
An equation stays true as long as you do the same thing to both sides, like adding the same weight to both pans of a balance. Adding or subtracting the same amount on both sides moves a term to the other side, where it appears with the opposite sign.
x + 7 = 9Collect every term containing x on the left.
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3 Subtract 7 from both sidesx = 2
Move the constant terms to the right.
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4 Check\begin{aligned}x = 2:\quad 17 = 17\quad\checkmark\end{aligned}
Substituting each solution back makes both sides equal.
Check by substitution
| x | Left side | Right side | |
|---|---|---|---|
| 2 | 17 | 17 | ✓ |
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