How do I solve the following simultaneous equations? y = 2x -3 and 2x + 3y = 23
Equation 1 : y = 2x -3 Equation 2: 2x +3y = 23To solve these equations you use a method called substitution The information from the 1st equation is used by the 2nd one Sub in the formula for y like so: 2x + 3 (2x -3) = 23Expand the brackets/multiply out2x + 6x - 9 = 23Bring all the algebraic terms on one side 8x = 32Divide by 8 x=4 Then substitute this value into equation 1 to find out what y equals y = 2(4) - 3 = 8-3 = 5y = 5
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