Solve 7x + 15 = −34

The solution of 7x + 15 = −34 is x = -7.

7x + 15 = -34\ \Rightarrow\ x = -7

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The lines y = 7x + 15 and y = -34 meet at x = -7. The solution of the equation is the x-coordinate of the point where the two sides are equal.

How to work it out

1
The goal is to get x alone. Undo the operations in the opposite order: first the addition, then the multiplication.
$7x + 15 = -34$
2
Subtract 15 from both sides:
$7x + 15 - 15 = -34 - 15 \ \Rightarrow\ 7x = -49$
3
Divide both sides by 7:
$\frac{7x}{7} = \frac{-49}{7} \ \Rightarrow\ x = -7$
4
Check: put x = -7 back into the equation.
$7\cdot(-7) + 15 = -49 + 15 = -34 \checkmark$

LaTeX source of the formulas on this page

\[ 7x + 15 = -34\ \Rightarrow\ x = -7 \]
\[ 7x + 15 = -34 \]
\[ 7x + 15 - 15 = -34 - 15 \ \Rightarrow\ 7x = -49 \]
\[ \frac{7x}{7} = \frac{-49}{7} \ \Rightarrow\ x = -7 \]
\[ 7\cdot(-7) + 15 = -49 + 15 = -34 \checkmark \]

Trying values of x in 7x + 15 = −34

x	7x + 15	Equals -34?
-9	-48	no
-8	-41	no
-7	-34	yes
-6	-27	no
-5	-20	no

Questions

What is x in 7x + 15 = −34?

The solution of 7x + 15 = −34 is x = -7.

How do you solve 7x + 15 = −34?

Subtract 15 from both sides to get 7x = -49, then divide both sides by 7 to get x = -7.

How do I check the answer?

Replace x by -7: 7(-7) + 15 = -34, which is -34.

Solve 7x + 15 = −34

How to work it out

Trying values of x in 7x + 15 = −34

Questions

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