Answer:
y = 2x + 3.5
Step-by-step explanation:
Step 1: find the slope
8y + 4x = 64
8y = 64 - 4x
Make y the subject of the formula
y = (64 - 4x)/8
y = ( -4x + 64)/8
Separate to get slope
y = -4x/8 + 64/8
y = -x/2 + 8
Slope is the coefficient of x
m = -1/2
Note: if two lines are perpendicular to the other , it is negative reciprocal to each other
m = 2
Using the point slope form equation
y - y1 = m(x - x1)
y - y1 = 2(x - x1)
Substitute the point
( 3.5 , 0)
x1 = 3.5
y1 = 0
y - 3.5 = 2( x - 0)
open the bracket
y - 3.5 = 2x - 0
y = 2x - 0 + 3.5
y = 2x + 3.5
The equation of the line is
y = 2x + 3.5
Answer:
Time machine one = 3.56
Time machine two = 4.56
Step-by-step explanation:
Let machine 2 do the job in x hours
Let machine 1 do the job in x - 1 hours.
The general formula for this problem is
Time = A*B/(A + B)
Givens
Time = 2 hours
B = x hours alone
A = x - 1 hours alone.
#################
x *( x - 1)
======= = 2
(x + x - 1)
(x^2 - x)/(2x - 1) = 2
x^2 - x = 2(2x - 1)
x^2 - x = 4x - 2
x^2 - 5x + 2 = 0
a = 1
b = - 5
c = 2
This gives 2 roots
x = 4.56
x = 0.43
The second root will not work because when 1 is subtracted from 0.43 the time give will be minus, which won't work.
Time for machine 2 is 4.56
The time for machine 1 is 3.56
Check
(A * B)/(A + B) = 2
A = 4.56
B = 3.56
Time = 4.56*3.56/(4.56 + 3.56)
Time = 16.2336/(8.12)
Time = 1.9992
The rounding error in the check comes from the rounding error in the times.
2(2)2(3)2(4)=192 because you're multiplying everything together in order to find your answer and also because the variables which are the letters represent the numbers that need to be multiplied idk if that made sense but that's the answer lol
Answer:
Q1: 48
Q2: 59
Step-by-step explanation: