Answer:
Billy used 28 mins 30 sec to mow the lawn and Bobby used 43 mins 30 sec to now the lawn both within 72 mins
Step-by-step explanation:
let x represent Billy
let x+15 represent Bobby
x + x + 15 = 72
2x = 72 - 15
2x = 57
2x/2 = 57/2
x = 28.5 minutes = 28 minutes 30 seconds
Bobby = x + 15
= 28.5 + 15
= 43.5 minutes= 43 minutes 30 seconds
Answer:
the correct answer is , 4(20+3)
Step-by-step explanation:
Answer:
The answer is D.
Step-by-step explanation:
Because Chicago and Miami are the only places on the table that are both in North america and are cities.
Answer: x = 4 and x = -3/2
Procedure:
1) Given: 2x^2 - 5x - 12 = 0
2) Multiply both sides by : 2(2x^2) - 2(5x) - 2(12) = 0
3) Rearrange: (2x)^2 -5(2x) - 24 = 0
4) Notice that the common factor is (2x)
5) Set the parenthesis with the common factor inside:
(2x ) (2x ) =0
6) The first sign is the same sign of the second term of the trinomial, which is negative, the second sign is the product of the signs of the second and the third terms of the polynomial, which is (-)*(-) = + (positive)
(2x - )(2x + ) = 0
7) find two numbers that sum up - 5x and its product is -24.
- 8 + 3 = - 5
(-8)(+3) = -24
=> the numbers in the factors are -8 and +3
(2x - 8) (2x + 3) = 0
That is the factored equation. Now you can solve
8) a) 2x - 8 = 0 => 2x = 8 => x = 8/2 => x = 4
b) 2x + 3 = 0 => 2x = - 3 => x = - 3/2
Answer: the two solutions are x = 4 and x = -3/2
