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Solve the simultaneous equation: 2x +y =18; x-y=6. (3)

Turn x-y=6 into y=6+x.2) Insert y=6+x into 2x+y=18; get 2x+6+x=183) Turn the latter equation into 3x=18- 6=124) Divide 12 by 3 to get x=45) Insert x=4 into y=6+x into y=106) Conclude with x=4 and y=...

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(i) Find the gradient of the straight line passing through the points: (0,3) and (9,21). (ii) Write down the equation of the line in form y = mx + c

(i) To find the gradient of a straight light, we take any two (different) points on the straight line and compute the change in Y divided by the change in X. So here this is; (21-3)/(9-0) = 18/9 = 2. So t...

Answered by Charlie G. • Maths tutor

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Solve the simultaneous equations; 2x + y = 18; x + 3y = 19.

Start by selecting a variable to eliminate from the equations. --> Select x in this case.Take the second equation and multiply by 2. --> 2x + 6y = 38Subtract the first equation from this answer. --&...

Answered by Mark A. • Maths tutor

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How can you factorise x^2-9

First, we notice how there is only an 'x²' term and a number in this expression. Also notice that the number, 9, is a square number. Whenever you have an expression that looks like 'x²

Answered by Rebecca A. • Maths tutor

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Solve the simultaneous equations 6x - 27 = 15 and 4x + 3y = -3.

Initially we have two unknown variables, so we want to eliminate one of the variables (x) to solve for the other (y). The LCM of 6 and 4 is 12, so multiply each equation such that the coefficient of x is ...

Answered by Alannah C. • Maths tutor

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