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5x-y = 3 "0.2x plus 0.3y = negative 0.9 Quadratic equation with two variables
y=5x-3
Substituting
0.2x+0.3(5x-3)=-0.9
0.2x+1.5x-0.9=-0.9
1.7x=0
So x = 0
y=5x-3=-3
2X + 3Y equals 7 and 5x-y equals 9
Is a solution of equation 5x ay equal to 7. Then the value of a is
2x+3y=7,5x-y=9
x=2,y=1
A solution of equation 5x ay = 7
5*2-a*1=7
a=3
Given that X / 3 = Y / 5 = Z / 7 is not equal to 0, then 2x + 3Y + 4Z / 5x-3y + Z =?
x/3=y/5=z/7=k
x=3k,y=5k,z=7k
2x+3y+4z/5x-3y+z
=(6k+15k+28k)/(15k-15k+7k)
=7
For the system of equations x + ay + 1 = 0bx − 2Y + 1 = 0 of X, y, there are innumerable solutions, then the values of a and B are ()
A. a=0，b=0B. a=-2，b=1C. a=2，b=-1D. a=2，b=1
By subtracting the equations x + ay + 1 = 0bx − 2Y + 1 = 0 about X and y, it is obtained that: (1-B) x + (a + 2) y = 0, ∵ the equations have innumerable solutions, ∵ 1-B = 0, a + 2 = 0, the solutions are a = - 2, B = 1
RELATED INFORMATIONS
- 1. Given that the solution of the system of equations x-2y = 0, BX + ay = 2 is the same as that of the system of equations 2x + y = 5, ax + ay = 1, find the value of a and B
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