Answer:
r = - 2.5

Step-by-step explanation:
21r - 7 - r + 5 = - 52
20r - 2 = - 52
20r - 2 + 2 = - 52 + 2
20r = - 50
20r ÷ 20 = - 50 ÷ 20
r = - 2.5
So easy so easy so easy so easy so easy so easy so easy 9
Answer:
for second question
first length is 9cm
Area=l*b
= 9cm *9cm
=81<em><u>cm</u></em>
then, For semicircle
radius is 9 cm
area= 1/2*9cm
now , area of two semi circle = 2*1/2*9
= 9 cm
now area of shaded = 81-9
=72
X=5+y
x+y=-15
subsitute 5+y for x
5+y+y=-15
5+2y=-15
minus 5 from both sides
2y=-20
divide both sides by 2
y=-10
sub back
x=5+y
x=5-10
x=-5
the numbers are -10 and -5