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Solve the simultaneous equations x+y=8 and 3x-y=4.

Notice that y has the same coefficient (ignoring the sign) in both equations. So, we will use the elimination method. The elimination method means that we will combine the two equations to eliminate the y va...
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Answered by Fiona S. • Maths tutor
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Make x the subject of the formula: y=(x+5w/2)^0.5

First recognise that (x+5w/2)^0.5 is the same as the square root of (x+5w/2). Then square both sides of the equation to get: y^2=(x+5w/2).Multiply both sides by 2 to eliminate the fraction from the RHS: 2y^2...
CW
Answered by Charles W. • Maths tutor
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3x + 2y =4 and 4x - 17 = 5y. Solve the simultaneous equations.

write out each equation one underneath the other so that the x’s are in one column and the y’s are in another.2) we also need to make sure that the numbers are also aligned up3) for 4x - 17 = 5y, we can add ...
Answered by • Maths tutor
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What is the derrivative (dy/dx) of the equation 2 = cos 4x - cos 2y in terms of x and y?

A common C4 question where the student would need to use implicit differentiation to obtain an equation with the derrivative in it. 0 = -4sin4x + 2(dy/dx)sin2y. Then all that is required is rearranging the e...
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Answered by Arsh Y. • Maths tutor
3702 Views

How do you know when to use sin, cos and tan in trigonometry?

Best way to remember it is: soh, cah and toa.Where soh means that the s ine of the angle is equal to the length of the o pposite side divided by the length of the h ypotenuse. Cah means that the c osine of t...
Answered by • Maths tutor
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