Hi there!
To solve this problem using substitution, we need to set x equal to a value and substitute it into the other equation.
Since
x - 4y = 5,
x = 5 + 4y
3x - 7y = 10
3(5 + 4y) - 7y = 10
15 + 12y - 7y = 10
15 + 5y = 10
5y = -5
y = -1
Now that we know y is -1, we can substitute it back into the equation to find x:
y = -1
x - 4y = 5
x - 4(-1) = 5
x - (-4) = 5
x + 4 = 5
x = 1
So, your answers are x = 1 and y = -1.
Hope this helps!
Answer:
7
/8
0.875
Step-by-step explanation:
Answer:
3 hours
Step-by-step explanation:
Recall:
Distance = speed x time
we are given that speed = 18 km/h and distance = 54 km.
hence,
54 = 18 x time (divide both sides by 18 and rearrange)
time = 54/18 = 3 hours