You would substitute the given value of “y” into the equation of -14x+y=16
-14x+5x-2=16
Then you would solve for “x”
x=2
You would then substitute the value of “x” into the equation to solve for “y”
y=5(2)-2
Which would then give you a value for “y”
y=12
So the answer is (2,12)
I need more information for help you answer this
Givens
<em><u>Slower car</u></em>
r = r
t = 12 hours
d = ?
<em><u>Faster car</u></em>
r = r + 20
t = 8 hours
d = ?
It doesn't matter what the exact distance is. You just have to know that the 2 distances are equal ie going to the mountains from his home is the same distance as going from the mountains to his home.
d = r * t
r * 12 hours = (r + 20)* 8 hours. Remove the brackets on the right
r*12 = 8r + 20*8
r*12 = 8*r + 160
r*12 - 8r = 8r - 8r + 160
4r = 160
r = 40 miles / hour
=================
Slower Ride determines the distance.
d = r*t
d = 40 * 12
d = 480
Check
Use the faster rate (r + 20) = 40 + 20 = 60 mph
60 * 8 = 480. Both distances work out to be the same.
Saw A = 150 planks/30 seconds = 5 planks per second
Saw B = 130 planks/ 13 seconds = 10 planks per seconds
5 + 10 = 15 planks per second total
225 planks / 15 planks per second = 15 seconds
Answer: 15 seconds
