B
(6x)
By the
(x+6)
the
triangle is equal to 180°. Therefore,
m/A+m/B+m/C = 180°. Using
the sum of the angles in a
(6x)˚ +90° + (x + 6)˚° = 180°. To
solve for x, first combine like terms to get 7x +96= 180. Using the
, 7x = 84. Then, using the division
property of equality, x = 12. To find the measure of angle A, use the
substitution property to get m/A=
6(12)˚. Finally,
simplifying the expression gets
sm/A=72°.
substitution property
subtraction property of equality
multiplication property of equality triangle sum theorem
distributive property division property of equality