Solve 8x − 1 = −65

The solution of 8x − 1 = −65 is x = -8.

8x - 1 = -65\ \Rightarrow\ x = -8

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

The lines y = 8x − 1 and y = -65 meet at x = -8. 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 subtraction, then the multiplication.
$8x - 1 = -65$
2
Add 1 to both sides:
$8x - 1 + 1 = -65 + 1 \ \Rightarrow\ 8x = -64$
3
Divide both sides by 8:
$\frac{8x}{8} = \frac{-64}{8} \ \Rightarrow\ x = -8$
4
Check: put x = -8 back into the equation.
$8\cdot(-8) - 1 = -64 - 1 = -65 \checkmark$

LaTeX source of the formulas on this page

\[ 8x - 1 = -65\ \Rightarrow\ x = -8 \]
\[ 8x - 1 = -65 \]
\[ 8x - 1 + 1 = -65 + 1 \ \Rightarrow\ 8x = -64 \]
\[ \frac{8x}{8} = \frac{-64}{8} \ \Rightarrow\ x = -8 \]
\[ 8\cdot(-8) - 1 = -64 - 1 = -65 \checkmark \]

Trying values of x in 8x − 1 = −65

x	8x − 1	Equals -65?
-10	-81	no
-9	-73	no
-8	-65	yes
-7	-57	no
-6	-49	no

Questions

What is x in 8x − 1 = −65?

The solution of 8x − 1 = −65 is x = -8.

How do you solve 8x − 1 = −65?

Add 1 to both sides to get 8x = -64, then divide both sides by 8 to get x = -8.

How do I check the answer?

Replace x by -8: 8(-8) − 1 = -65, which is -65.

Solve 8x − 1 = −65

How to work it out

Trying values of x in 8x − 1 = −65

Questions

Similar equations