Answer:
Step-by-step explanation:
x/4-y/2=8, x-2y=32, x=32+2y
x/2+3y/4=-5, 2x+3y=-20, x=(-20-3y)/2
32+2y=(-20-3y)/2
64+4y=-20-3y
7y=-84
y=-12, since x=32+2y
x=32+2(-12), x=32-24=8
So the solution is the point (8, -12)
Answer:
Use 49 ounces of the 14% allow and 41 ounces of the 23% alloy.
Step-by-step explanation:
Each ounce of the 14% copper contains 0.14 ounce of pure copper.
Each ounce of the 23% copper contains 0.23 ounce of pure copper.
Each ounce of the 18.1% copper contains 0.181 ounce of pure copper.
Use x ounces of the 14% and y ounces of the 23% to make 90 ounces of 18.1% alloy.
x+y = 90
y = 90-x
0.14x + 0.23y = 0.181·90
0.14x + 0.23(90-x) = 16.29
0.14x + 20.7 - 0.23x = 16.29
-0.09x + 20.7 = 16.29
4.41 = 0.09x
x = 49
y = 90-x = 41
Use 49 ounces of the 14% allow and 41 ounces of the 23% alloy.
The value of x is 5/8.
<u>Step-by-step explanation</u>:
Given,
- The lines PQ and RS are parallel to each other.
- slope of PQ= x-1/4
- slope of RS = 3/8
The slopes of parallel lines are equal.
slope of PQ = slope of RS
⇒ x-1/4 = 3/8
⇒ (4x-1)/4 = 3/8
⇒ 8(4x-1) = 4(3)
⇒ 32x-8 = 12
⇒ 32x = 20
x = 20/32
x = 5/8
C is the rigth answer because all the other three has two x values in common. :)
y=-1/2x-4
I could be wrong. Not my strong subject.
-Seth
