Answer:
x = 16
z = 90°
Explanation:
The angle with the measure (10x - 70) and the angle with measure (5x+10) are supplementary angles and their sum is equal to 180 so it's safe to write the following equation:
10x - 70 + 5x + 10 = 180 add like terms
15x - 60 = 180 add 60 to both sides
15x = 240 divide both sides by 15
x = 16
The angle represented with z and the angle with measure (10x - 70) are also supplementary because they are on a straight line so we can write the following equation to find the value of z:
z + (10*16-70) = 180 calculate inside the parenthesis
z + 90 = 180 subtract 90 from both sides
z = 90°