Solve 7x − 14 = −77

The solution of 7x − 14 = −77 is x = -9.

7x - 14 = -77\ \Rightarrow\ x = -9

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

The lines y = 7x − 14 and y = -77 meet at x = -9. 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.
$7x - 14 = -77$
2
Add 14 to both sides:
$7x - 14 + 14 = -77 + 14 \ \Rightarrow\ 7x = -63$
3
Divide both sides by 7:
$\frac{7x}{7} = \frac{-63}{7} \ \Rightarrow\ x = -9$
4
Check: put x = -9 back into the equation.
$7\cdot(-9) - 14 = -63 - 14 = -77 \checkmark$

LaTeX source of the formulas on this page

\[ 7x - 14 = -77\ \Rightarrow\ x = -9 \]
\[ 7x - 14 = -77 \]
\[ 7x - 14 + 14 = -77 + 14 \ \Rightarrow\ 7x = -63 \]
\[ \frac{7x}{7} = \frac{-63}{7} \ \Rightarrow\ x = -9 \]
\[ 7\cdot(-9) - 14 = -63 - 14 = -77 \checkmark \]

Trying values of x in 7x − 14 = −77

x	7x − 14	Equals -77?
-11	-91	no
-10	-84	no
-9	-77	yes
-8	-70	no
-7	-63	no

Questions

What is x in 7x − 14 = −77?

The solution of 7x − 14 = −77 is x = -9.

How do you solve 7x − 14 = −77?

Add 14 to both sides to get 7x = -63, then divide both sides by 7 to get x = -9.

How do I check the answer?

Replace x by -9: 7(-9) − 14 = -77, which is -77.

Solve 7x − 14 = −77

How to work it out

Trying values of x in 7x − 14 = −77

Questions

Similar equations