When using substitution the answer to y0.5x plus 2 -y-2x plus 4 is y = -2 (x-1.
Thanks to the browser, it is not possible to tell what the inequalities are.
Without any equality signs the given expression can't be considered to be straight line equations.
It is an expression in two variables, x and y.
If you mean: y = 2x+5 then it is a straight line equation.
If you mean: y = 6x+11 and y = 2x+7 Then by substitution: x = -1 and y = 5
Since there is no equality (or inequality) sign in the question, there is no equation or inequality) and therefore nothing which can be solved.
The y value will equal 15, when x = 7
y2x - just double the coordinate of y to get x. xy12 - i have no idea
If you mean: y = x^2+4x+3 and y = 2x+6 Then the solution is: x = 1 or x = -3
If you mean: y = 2x+8 then it is a straight line equation whereas 2 is the slope and 8 is the y intercept
If you mean: y = 2x and 2y = -x+4 then they are positive and negative straight line equations
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