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solve the simultaneous equations 3x+7y=18 and 7x+9y=8

3x+7y=18 (eqn 1) -multiply by 7-> 21x+49y=126 (eqn 1*) 7x+9y=8 (eqn 2) -multiply by 3-> 21x+27y=24 (eqn 2*) (eqn 1*)-(eqn 2*) --> 22y=102 therefor y=51/11 sub in this y value back into (eqn1) -->...
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Answered by Radhika S. • Maths tutor
3957 Views

Solve the following simultaneous equations: (1) 4x+y=7 and (2) 3x+2y=9

This question can be answered by the elimination method. I will choose to eliminate 'y' in this case. Firstly, multiply equation (1) by 2, resulting in 8x+2y=14. Now we can subtract eqaution (2): 3x+2y=9 fro...
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Answered by Alex D. • Maths tutor
6119 Views

Find the value of dy/dx at the point where x = 2 on the curve with equation y = x^ 2 √(5x – 1).

Here we must use the product rule to differeniate because x appears in both terms of the equation, therefore both parts must be differentiated. So we will set u= x 2 and v= (5x-1)^(1/2) written like this mak...
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Answered by Lucy T. • Maths tutor
13303 Views

Solve for x: 4 x + 1 = 2 x + 12

The best way to answer these kind of questions is by moving all the unknowns to one side. In this case, the only unknown is x, so we should start by moving all the x's to one side. Since there are 4x's on th...
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Answered by Tejas K. • Maths tutor
3942 Views

How do I find the derivative of two functions multiplied by each other?

To find the derivative of two functions multiplied by each other we would use the product rule. The product rule: (fg)'(x) = f '(x).g(x) + f(x).g'(x) First we need to split our function into the two parts th...
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Answered by Eleanor S. • Maths tutor
4979 Views