Answer:
<h2>
55.39 units ^2</h2>
Step-by-step explanation:
A=pi*r^2
A=3.14*4.2^2
A=3.14*17.64
A=55.3896
A≈55.39 units ^2
Answer:
6.28
Step-by-step explanation:
Answer:
105
Step-by-step explanation:
105
Step-by-step explanation:
Let m = man's age right now
d = daughter's age right now
m-2 = 6(d-2) => m = 6d -12 +2 = 6d-10
m+18 = 2(d+18) => m = 2d+36-18 = 2d+18
6d-10 = 2d+18
4d = 28
d = 7
m = 32
Answer:
1)
(x + 3)(x + 4) = x^2 + 4x + 3x + 12 = x^2 + 7x + 12
Instead of multiplying 3 and 4 the student added them which gave them the answer of 7 when the correct answer is 12.
2)
a) x^2 + x - 2
b) x^2 - 7x + 10
c) 4x^2 - 1
d) x^2 + 10x + 25
Step-by-step explanation:
a. (x - 1)(x + 2)
x(x) - 1(x) + 2(x) - 1(2)
x^2 - 1x + 2x - 2
x^2 + x - 2
------------------------------------------
b. (x - 5)(x - 2)
x(x) - 5(x) - 2(x) - 5(-2)
x^2 - 5x - 2x + 10
x^2 - 7x + 10
------------------------------------------
c. (2x + 1)(2x - 1)
2x(2x) + 1(2x) - 1(2x) + 1(-1)
4x^2 + 2x - 2x - 1
4x^2 - 1
------------------------------------------
d. (x + 5)^2
(x + 5)(x + 5)
x(x) + 5(x) + 5(x) + 5(5)
x^2 + 5x + 5x + 25
x^2 + 10x + 25