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
Answer:
D
Step-by-step explanation:
The starting point is B and the ray extends towards A.
So the asnwer is D.
Answer:
Multiples of 120 are 120, 240, 360, 480, 600, 720, 840 etc; Multiples of 150 are 150, 300, 450, 600, 750, 900 etc; Therefore, the least common multiple of 120 and 150 is 600.
Least common multiple (LCM) of 19600 and 19619 is 384532400.
