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Simultaneously solve the equations 3x+2y=36 and 5x+4y=64

The easiest way to solve a simultaneous equation is by the method of substitution. First of all, we take the first equation, and rearrange it so that it is in terms of y. Or, in other words, rearrange it so ...
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Answered by Finlay S. • Maths tutor
12492 Views

Differentiate sin(5x) and 3cos(x) and 3tan(5x)

sin cos -sin -cos (down is differentiate and up is integrate) so, y = sin5x dy/dx = 5cos5x y=3cox dy/dx = -3sinx y=3tan5x dy/dx = 15sec 2 (5x) (remember sec(x) is the reciprocal of cos(x))
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Answered by Abi C. • Maths tutor
5223 Views

Expand and simplify the following: 3(z + 6) – 2(4z + 1)

Expand the brackets: (3z + 18) - (8z + 2) Simplify: 16 - 5z
RW
Answered by Ryan W. • Maths tutor
4252 Views

Make a the subject of a+3=(2a+7)/r

Times both side by r to get ar+3r=2a+7 Subtract 2a and 3r from both side to bring a to one side, ar-2a=7-3r Factorise the left handside, a(r-2)=7-3r Divide both side by r-2, a=(7-3r)/(r-2)
AH
Answered by Arafatul H. • Maths tutor
5540 Views

What is the probability of picking a red ball twice from a bag of 6 blue balls and 3 red balls, without replacement.

The probability of picking a ball from a bag is the number of balls of that colour divided by the total number of balls. Therefore in the first instance, the probability of a red ball is 3/9 or 1/3rd. If tha...
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Answered by Toby F. • Maths tutor
41609 Views