Which is the following have the correction solution? select all that apply.
question 1 options:
a)3x+7=10; x=−1
b)5(x+4)−x=40; x = 5
c)x−34=3; x=12
d)7=13x+5; x=6

(b) is correct.

Step-by-step explanation:

We substitute the given  value of x in each equation and see if they fit.

a) 3x + 7 = 10   Plug in x = -1:

3(-1) + 7 = 4  so this solution is incorrect>

b) is correct because

5(5+4) - 5 = 45 - 5 = 40.

c and d are incorrect.

x = -3

y = -18

step-by-step explanation:

to solve by substitution, substitute one variable and solve for the other. then substitute again to find the remaining variable.

x-1/3(3x-9) = -3 since y=3x-9 substittute y.

x-1/3(3x-9)=-3

x + x +3 = -3

2x+3=-3

2x+3-3= -3-3

2x=-6

x=-3

substitute again into y=3x-9

y=3(-3)-9

y=-9-9

y=-18