Solve 10x + 15 = −15

The solution of 10x + 15 = −15 is x = -3.

10x + 15 = -15\ \Rightarrow\ x = -3

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

The lines y = 10x + 15 and y = -15 meet at x = -3. 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.
$10x + 15 = -15$
2
Subtract 15 from both sides:
$10x + 15 - 15 = -15 - 15 \ \Rightarrow\ 10x = -30$
3
Divide both sides by 10:
$\frac{10x}{10} = \frac{-30}{10} \ \Rightarrow\ x = -3$
4
Check: put x = -3 back into the equation.
$10\cdot(-3) + 15 = -30 + 15 = -15 \checkmark$

LaTeX source of the formulas on this page

\[ 10x + 15 = -15\ \Rightarrow\ x = -3 \]
\[ 10x + 15 = -15 \]
\[ 10x + 15 - 15 = -15 - 15 \ \Rightarrow\ 10x = -30 \]
\[ \frac{10x}{10} = \frac{-30}{10} \ \Rightarrow\ x = -3 \]
\[ 10\cdot(-3) + 15 = -30 + 15 = -15 \checkmark \]

Trying values of x in 10x + 15 = −15

x	10x + 15	Equals -15?
-5	-35	no
-4	-25	no
-3	-15	yes
-2	-5	no
-1	5	no

Questions

What is x in 10x + 15 = −15?

The solution of 10x + 15 = −15 is x = -3.

How do you solve 10x + 15 = −15?

Subtract 15 from both sides to get 10x = -30, then divide both sides by 10 to get x = -3.

How do I check the answer?

Replace x by -3: 10(-3) + 15 = -15, which is -15.

Solve 10x + 15 = −15

How to work it out

Trying values of x in 10x + 15 = −15

Questions

Similar equations