Answer:
Step-by-step explanation:
Hello There!
Remember: sum of interior angles of a triangle = 180
so to find x we use this equation
180 = 90 + 7x + 5 + 9x + 5 ( the little square in the triangle indicates that the angle is a right angle. right angles have a measure of 90 so that's where the 90 came from.)
now we solve for x
step 1 combine like terms
90 + 5 + 5 = 100
7x + 9x = 16x
now we have 180 = 16x + 100
step 2 subtract 100 from each side
180 - 100 = 80
100 - 100 cancels out
now we have 80 = 16x
step 3 divide each side by 16
80/16 = 5
16x/16=x
we're left with x = 5
Finally we plug in 5 into x for angle a
7(5)+5
7*5=35
35+5=40
so we can conclude that the measure of angle A is 40 degrees