Answer:
[tex]\angle A=113\textdegree[/tex]
Step-by-step explanation:
We know that ∠A and ∠B are vertical angles.
Remember that vertical angles have the same measure. So:
[tex]\angle A=\angle B[/tex]
Substitute them for their equations:
[tex]7x-20=6x-1[/tex]
Solve for x. Add 20 to both sides:
[tex]7x=6x+19[/tex]
Subtract 6x from both sides. So, the value of x is:
[tex]x=19[/tex]
To find ∠A, we can use its equation again:
[tex]\angle A=7x-20[/tex]
Substitute 19 for 7:
[tex]\angle A=7(19)-20[/tex]
Multiply and subtract:
[tex]\angle A=133-20=113\textdegree[/tex]
So, the value of ∠A is 113°.
And we're done!
