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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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Relative to a fixed origin O, the point A has position vector (8i+13j-2k), the point B has position vector (10i+14j-4k). A line l passes through points A and B. Find the vector equation of this line.

The vector equation of any line is composed of the addition of a point on the line and some distance in the direction of the line, in the form y=(x,y,z) +d(x_1, y_1, z_1), where (x,y,z) is any point on th...

Answered by Carlota S. • Maths tutor

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Given the ratio of x : y is 7 : 4 and x + y = 88. Work out the value of x – y

7x = 4yx=4y/7If we insert this into our other equation.4y/7 + y = 8811y/7 =88y = 56As we knowx =4y/7X= 4*56/7 = 32Then we can work out the answer X - Y = 32 - 56 = -24

Answered by Salih K. • Maths tutor

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