Best Answer

Given:

15x - 20y = -1

15y = 2 + 5x

Then:

15x -20(2 + 5x)/15 = -1

∴15x -40/15 - 100x/15 = -15/15

∴225x/15 - 100x/15 = 40/15 - 15/15

∴125x = 25

∴x = 1/5

Check:

15(1/5) - 20(1/5) = -1

∴3 - 4 = -1

∴-1 = -1

Q: Solve by the substitution method 15x-20y equals -1 15y equals 2 plus 5x?

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x+y=5

by elimination,substitution or through the matrix method.

If: x+y = 4 and y = 2x+1 Then: 4-x = 2x+1 => 3 = 3x => 1 = x So by substitution: x = 1 and y = 3

-2

You cant solve it unless it is an equation. To be an equation it must have an equals sign.

Related questions

x+y=5

(2,3)

Use the substitution method to solve the system of equations. Enter your answer as an ordered pair.y = 2x + 5 x = 1

by elimination,substitution or through the matrix method.

You can solve lineaar quadratic systems by either the elimination or the substitution methods. You can also solve them using the comparison method. Which method works best depends on which method the person solving them is comfortable with.

If: x+y = 4 and y = 2x+1 Then: 4-x = 2x+1 => 3 = 3x => 1 = x So by substitution: x = 1 and y = 3

That's exactly the purpose of the substitution method ... to get an equation with one less variable. When you have it, you solve it for the variable that's left.

y= -4x-7 y=3x 3x= -4x-7 3x+4x=7 7x=7 x=1

-2

You solve this by theoretically diverting the hypotenuse of the x divided by the overall beneficial procedure of y

You cant solve it unless it is an equation. To be an equation it must have an equals sign.

This is not Calculus.y=7(Already solved)substiute y=7 into y=8xtherefore 7 = 8xtherefore x = 7/8