Solve 12x + 5 = −115

The solution of 12x + 5 = −115 is x = -10.

12x + 5 = -115\ \Rightarrow\ x = -10

Explain it step by step in chat Make a short video of it

The lines y = 12x + 5 and y = -115 meet at x = -10. 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.
$12x + 5 = -115$
2
Subtract 5 from both sides:
$12x + 5 - 5 = -115 - 5 \ \Rightarrow\ 12x = -120$
3
Divide both sides by 12:
$\frac{12x}{12} = \frac{-120}{12} \ \Rightarrow\ x = -10$
4
Check: put x = -10 back into the equation.
$12\cdot(-10) + 5 = -120 + 5 = -115 \checkmark$

LaTeX source of the formulas on this page

\[ 12x + 5 = -115\ \Rightarrow\ x = -10 \]
\[ 12x + 5 = -115 \]
\[ 12x + 5 - 5 = -115 - 5 \ \Rightarrow\ 12x = -120 \]
\[ \frac{12x}{12} = \frac{-120}{12} \ \Rightarrow\ x = -10 \]
\[ 12\cdot(-10) + 5 = -120 + 5 = -115 \checkmark \]

Trying values of x in 12x + 5 = −115

x	12x + 5	Equals -115?
-12	-139	no
-11	-127	no
-10	-115	yes
-9	-103	no
-8	-91	no

Questions

What is x in 12x + 5 = −115?

The solution of 12x + 5 = −115 is x = -10.

How do you solve 12x + 5 = −115?

Subtract 5 from both sides to get 12x = -120, then divide both sides by 12 to get x = -10.

How do I check the answer?

Replace x by -10: 12(-10) + 5 = -115, which is -115.

Solve 12x + 5 = −115

How to work it out

Trying values of x in 12x + 5 = −115

Questions

Similar equations