Can someone me with these two questions on substitution.

Number 23:

x=7

y=6

Number 24:

x=-6

y= -5

Step-by-step explanation:

Number 23: You have to make one of the equations have only one variable per side

x-y=1 to x=1+y     Then you put the 1+y in all the x's spots on the other equation

2(1+y)=14           Distribute the 2 to 1+y

2+2y=14            Subtract 2 from both sides

2y=12                 divide both sides by 2

y=6                     Now you fill in your answer for six to find the x

x-y=1

x-6=1                   Add six to both sides

x=7

Number 24: You have to have one equation have only one variable per side

x+3y=-36    to    x=-36-3y    now you fill in all the spots with x's with -36-3y

x-4y=-1              fill in the x spot

-36-3y-4y=-1         simplify the -3y and the -4y to -7y

-36-7y=-1                Add 36 to both sides

-7y=35                  Divide by -7 so the y will be positive

y=-5                 Now fill in the y with -5 to one of the equations

x-4y=-1           fill in the y spot

x-(-5)=-1           a negative by a negative is a positive so make the 5 positive

x+5=-1                Subtract 5 from both sides

x=-6

x = ±sqrt(10)

step-by-step explanation:

5 - 2x² = -15

subtract 5 from each side

5-5 - 2x² = -15-5

-2x^2   = -20

divide by -2 on each side

-2x^2   /-2= -20/-2

x^2 =10

take the square root on each side

sqrt(x^2 )=±sqrt(10)

x = ±sqrt(10)

check:

5 - 2x² = -15

+sqrt(10)

5 - 2(sqrt(10))² = -15

5 -2(10) = -15

5 -20 = -15

-15 = -15

-sqrt(10)

5 - 2(-sqrt(10))² = -15

5 -2(10) = -15

5 -20 = -15

-15 = -15

{x = -1/2 ,   y = -1

step-by-step explanation:

solve the following system:

{2 x + y = -2

{10 x - 3 y = -2

in the first equation, look to solve for y:

{2 x + y = -2

{10 x - 3 y = -2

subtract 2 x from both sides:

{y = -2 x - 2

{10 x - 3 y = -2

substitute y = -2 x - 2 into the second equation:

{y = -2 x - 2

{10 x - 3 (-2 x - 2) = -2

10 x - 3 (-2 x - 2) = (6 x + 6) + 10 x = 16 x + 6:

{y = -2 x - 2

{16 x + 6 = -2

in the second equation, look to solve for x:

{y = -2 x - 2

{16 x + 6 = -2

subtract 6 from both sides:

{y = -2 x - 2

{16 x = -8

divide both sides by 16:

{y = -2 x - 2

{x = -1/2

substitute x = -1/2 into the first equation:

{y = -1

{x = -1/2

collect results in alphabetical order:

answer:   {x = -1/2 ,   y = -1