x+6y=r−2x2(x+4)+2y=11+21(16+2x)In the system of equations, r is a constant. For what value of r does the system of linear equations have infinitely many solutions?
Q. x+6y=r−2x2(x+4)+2y=11+21(16+2x)In the system of equations, r is a constant. For what value of r does the system of linear equations have infinitely many solutions?
Substitute and Simplify: Substitute x from the first equation into the second equation to express everything in terms of y and r.x+6y=r−2x⇒3x+6y=rNow, double the first equation to get a comparable term for substitution.2(x+6y)=2(r−2x)⇒2x+12y=2r−4x⇒6x+12y=2r
Double Equations: Now let's simplify the second given equation.2(x+4)+2y=11+(21)(16+2x)⇒2x+8+2y=11+8+x⇒2x+2y=11+x⇒x+2y=11
Simplify Second Equation: Double the modified second equation to compare it with the modified first equation.2(x+2y)=2(11)⇒2x+4y=22Now, multiply this by 3 to match the terms with the first modified equation.3(2x+4y)=3(22)⇒6x+12y=66
Compare and Multiply: Compare the two modified equations.6x+12y=2r from the first modification6x+12y=66 from the second modificationFor the system to have infinitely many solutions, the two equations must be identical.So, set 2r equal to 66.
Set Equal and Solve: Solve for r.r=266r=33
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