X = 8
because 8 x 2 = 16
16 - 9 = 5
5 x 3 = 15
Answer:
equation: y=-4x-7
Step-by-step explanation:
y=-4x+b
solve for b using given coordinates on the line (-3, 5)
5=-4(-3)+b
b=-7
Y = 2x - 3 . . . (1)
y = -2x + 5 . . . (2)
Equating (1) and (2),
2x - 3 = -2x + 5
2x + 2x = 5 + 3
4x = 8
x = 8/4 = 2
x = 2
y = 2(2) - 3 = 4 - 3 = 1
y = 1
Solution = (2, 1)
Answer:
A (2,-2.5)
Step-by-step explanation:
Is 2 units right and 2.5 units down, right where point C is.
Short Answer: 18 minutes
Remark
The answer to this problem is less than the smallest time of the two people working together. that fact lets out C and D (38 minutes and 75 minutes). Now you have to choose 15 minutes and 18 minutes. There's a method. No guessing needed.
Givens
Let the time for Sophie = S
Let the time for Simon = M
Let the job to completion = 1
S = 45 minutes
M = 30 minutes
Step One
Convert minutes to hours.
45 minutes = 45 / 60 = 3/4 hour = 0.75 hour
30 minutes = 30 / 60 = 1/2 hour = 0.50 hour
Step Two
Set up the Equation
The formula is a form of job / hour.
Let the time = t that they both have to work
job = 1 in these problems.
1/S + 1/M = 1/t
1/0.75 + 1/0.5 = 1/t
Solve
1 ÷ 0.75 = 1.33333
1 ÷ 0.5 = 2
1.3333 + 2 = 3.33333
3.3333 = 1 / t Multlply both sides by t
3.3333*t = 1
t = 1 / 3.333333333
t = 0.3 of an hour
1 hour = 60 minutes
0.3 hours = x Cross Multiply
x = 60 * 0.3
x = 18 minutes
Answer working together it took them 18 minutes <<<<<