Yahoo Answers is shutting down on 4 May 2021 (Eastern Time) and the Yahoo Answers website is now in read-only mode. There will be no changes to other Yahoo properties or services, or your Yahoo account. You can find more information about the Yahoo Answers shutdown and how to download your data on this help page.
Can you please solve 4 simultaneous equations? And could you please help me cause I need to know how to do it for my quiz!?
And could you please show me how you do it
1. 3x- 2y=1
(x-2)^2 + (2y+3)^2 = 26
2. 2y + 3y=5
x^2 + xy - 2y = 10
3. x - 5y = 8
x^2 + 9y^2 + 3x = 30 + xy
1 Answer
- Barry GLv 76 years ago
1. 3x- 2y = 1
(x-2)^2 + (2y+3)^2 = 26
2y+3 = 3x+2
(x-2)^2 + (3x+2)^2 = 26
x^2-4x+4 + 9x^2+12x+4 = 26
10x^2+8x-18 = 0
5x^2+4x-9 = 0
(5x+9)(x-1) = 0
x = +1 or -9/5
2y = 3x-1 = +2 or -32/5
y = +1 or -16/5.
2. 2y + 3y=5
x^2 + xy - 2y = 10
I suspect the 1st eqn is typed incorrectly - maybe the 2nd also.
3. x - 5y = 8
x^2 + 9y^2 + 3x = 30 + xy
x = 5y+8
(5y+8)^2 + 9y^2 + 3(5y+8) = 30 + y(5y+8)
25y^2+80y+64 + 9y^2 + 15y+24 = 30 + 5y^2+8y
29y^2+87y+58 = 0
y^2+3y+2 = 0
(y+1)(y+2) = 0
y = -1 or -2
x = 5y+8 = +3 or -2.
