Answer:
(2,-3)
Step-by-step explanation:
I am not sure if you meant the first equation to be y or -y. I solved it as y.
y = x-5 -x -3y =7
I am going to take the second equation and write it as x =
-x - 3y = 7 Give equation
-x = 3y +7 Add 3y to both sides
x = -3y-7 Multiplied each term in the equation by -1 so that x could be positive
I am going to substitute -3y-7 for x in the first equation up above
y = x - 5
y = -3y -7 - 5 Substitute -3y-7 for x
y = -3y -12 Combined -7-5
4y = -12 Added 3y to both sides
y = -3 Divided both sides by 4.
I now know that y is -3, I will plug that into x = -3y-7 to solve for x
x = -3(-3) -7
x = 9-7 A negative times a negative is a positive
x = 2
If Gail practises swimming for 1 and 1/4 hours a day, then in a week she'll do:
1 1/4 * 7 = 5/4 * 7 = 35/4 = 8 3/4 [hours]
In other words she'll practice 8 hours and 45 minutes a week (assuming that she's still practicing on weekends).
X-intercept: 9
Y-intercept: 3
Intercepts are plotted on the graph below
Suppose there are 19x students, 1x teachers
19x+1x=400
20x=400
x=20
there are 20 teachers and 380 students.