Angle A = 3x - 10
Angle B = x
Their angle sum = 90° ( complementary angles form 90° )
This can be written in an equation as =
= 3x - 10 + x = 90
= 3x + × + ( -10 ) = 90
= 4x + (-10) = 90
= 4x = 90 + 10 ( transposing-10 from LHS to RHS changes-10 to +10 )
= 4x = 100
= x = 100 ÷ 4 ( transposing ×4 from LHS to RHS changes ×4 to ÷4 )
= x = 25
Angle A = 3x - 10
= 3 × 25 - 10
= 75 - 10
= Angle A = 65°
Angle B = x = 25°
Their sum = 65 + 25 = 90°
Therefore , the complementary angles , Angle A = 65° and Angle B = 25° .
Answer:
(a) = 11 cm
Step-by-step explanation:
The formula for finding the surface area of a regular pyramid is B + (1/2*P*l), with B being the area of the base, p being the perimeter of the base, and l being the slant of the pyramid.
The area of a pentagon can be solved using the formula 1/2*a*p, with a being the apothem and p being the perimeter of the pentagon.
- B + (1/2*80*15) = 1040
- B + 600 = 1040
- 1040 - 600 = 440 (440 is the area of pentagon)
- 1/2*a*(16*5) = 440
- 40*a = 440
- 440/40 = 11
The apothem is 11 cm. Hope this helps!
X= 12 + y
So then plug in
12 + y + y = 12
2y=0
Y= 0
X + 0 = 12
X= 12
this is prob wrong lol but hopefully it helps
Answer:
72
Step-by-step explanation:
Stacy has 30 marbles
Let m= the number of marbles that mallory has
stacy has 1/2 m -6
30 = 1/2 m -6
Add 6 to each side
30+6 = 1/2m
36 = 1/2m
Multiply each side by 2
72 = m
Mallory has 72 marbles
