How can a system of two linear equations be solved?

There are, mainly, three ways of doing it easily:
Substitution: It consists in modifying one of the equations in such a way that x is expressed in terms of y  (or y in terms of x) and then substitute that expression in the other equation. Elimination: it consists in multiplying on of the equations by a number such that when we add both equations x or y disappear, getting one equation with one variable easy to solve. Then, we substitute that solution into one of the equations. Graphically: it consists in drawing both lines, each one represented by one equation, and find out the point that have in common.

PA

Related Further Mathematics GCSE answers

All answers ▸

A curve has equation y = x^2 - 7x. P is a point on the curve, and the tangent to the curve at P has gradient 1. Work out the coordinates of P.


Simplify fully the expression ( 7x^2 + 14x ) / ( 2x + 4 )


A straight line passes trough the points A(-4;7); B(6;-5); C(8;t). Use an algebraic method to work out the value of t.


If the equation of a curve is x^2 + 9x + 8 = y, then differentiate it.