x+y = 10 and y = x+8
x+x+8 = 10
x+x = 10-8
2x = 2
x = 1
Substitute the value of x into the original equations to find the value of y:
So: x = 1 and y = 9
From first equation: x = 39 - 7ySubstitute this in second equation: 3(39 - 7y) - 2y = 2ie 117 - 21y - 2y = 2ie 115 = 23yie y = 5, making x = 4.
You cant solve it unless it is an equation. To be an equation it must have an equals sign.
Since the second equation is already solved for "y", you can replace "y" by "9" in the other equation. Then solve the new equation for "x".
x + 7y = 39 So x = 39 - 7y Substitute for x in the second equation: 3(39 - 7y) - 2y = 2 117 - 21y - 2y = 2 115 = 23y y = 5 Substitute this value for y back into the first equation: x + 7*5 = 39 x + 35 = 39 x = 4
y=4x=1Because:8x - y = 45x + 3y = 17You can rearrange the first equation to give:y = 8x - 4And substitute this into the second equation:5x + 3(8x - 4) = 17Expanded out:5x + 24x - 12 = 1729x - 12= 1729x = 29So x=1And because you know know x you can put that into an equation to find y:y = 8x - 4y= 8 - 4y= 4
From first equation: x = 39 - 7ySubstitute this in second equation: 3(39 - 7y) - 2y = 2ie 117 - 21y - 2y = 2ie 115 = 23yie y = 5, making x = 4.
3x - 2y = 20 Substitute x = 4y into this equation: 3(4y) - 2y = 20 ie 12y - 2y = 20 10y = 20 so that y = 2 and then x = 4y gives x = 2*4 = 8
You cant solve it unless it is an equation. To be an equation it must have an equals sign.
Since the second equation is already solved for "y", you can replace "y" by "9" in the other equation. Then solve the new equation for "x".
x + 7y = 39 So x = 39 - 7y Substitute for x in the second equation: 3(39 - 7y) - 2y = 2 117 - 21y - 2y = 2 115 = 23y y = 5 Substitute this value for y back into the first equation: x + 7*5 = 39 x + 35 = 39 x = 4
y=4x=1Because:8x - y = 45x + 3y = 17You can rearrange the first equation to give:y = 8x - 4And substitute this into the second equation:5x + 3(8x - 4) = 17Expanded out:5x + 24x - 12 = 1729x - 12= 1729x = 29So x=1And because you know know x you can put that into an equation to find y:y = 8x - 4y= 8 - 4y= 4
Using the quadratic equation formula:- x = 3.795831523 or x = -5.795831523
You'd need another equation to sub in
x + 2y = 7 So x = 7 - 2y Substitute this value for x in the second equation which then is: 2(7 - 2y) + y = 8 Simplify: 14 - 4y + y = 8 -3y = -6 y = 2 Put this value of y back into the first equation: x + 2*2 = 7 ie x + 4 = 7 x = 3
Using the quadratic equation formula: x = 8.42 or x = -1.42
You cannot solve one linear equation in two variables. You need two equations that are independent.
x=1, y=1