Answer:
7 and 6/8
Step-by-step explanation:
You have to use this sign <
3 days. You can’t do two because that’s not a whole number. However 63 divided by 3 is 21 which is his best plan for the most pages in the fewest days.
This is a simultaneous system of two linear equations with two unknowns, as the number of unknowns equals the number of equations, we can solve it:
y = 5x + 21
y = -7x - 15
we can equate both equations, given the fact that both are equal to y:
y = y
5x + 21 = -7x - <span>15
</span>and solving for x:
5x + 7x = -15 - 21
12x = -36
x = -36/12
x = -3
then we substitute this result in the original equation:
y = 5x + <span>21
</span>y = 5(-3) + <span>21
</span>y = -15 + 21
y = 6
hence the solution is x = -3 and y = 6