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How do you expand brackets?

The easiest method to expand brackets would be to remember FOIL! F - First O - Outside I - Inside L - Last Okay, so lets say you want to expand (3x+1)(2x+3), we'll fist multiply the f irst term of each brack...
CG
Answered by Connor G. Maths tutor
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There are 20 balls in a bag. The probability is 0.25 of picking a red ball. If one more red ball is added, what is the new probability of picking a red ball at random?

Convert 0.25 into a fraction where 20 is the denominator as there are 20 balls in total in the bag. 0.25 is the same as 1/4 and to convert this to 20 as the denominator multiply both the top and the bottom b...
AL
Answered by Alex L. Maths tutor
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The area of a square is 49cm^2. The perimeter of the square is equal to the circumference of a circle. what is the radius of the circle?

This is a geometry question. We know that a square has 4 equal sides of x, and that it's area is given by A=x 2 . So we can work out the length of the side of the square. x=sqrt(49) = 7 We are told this is e...
JC
Answered by Julia C. Maths tutor
16275 Views

Solve these simultaneous equations: y=3x-10; y=2x+5

Method 1 (algebraically): Since we have "y=" at the start of both equations, we can substitue one into the other to get 3x-10=2x+5 Then we want all the x terms on one side of the equation, and all ...
CW
Answered by Catherine W. Maths tutor
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Solve the simultaneous equation: 3x+y=-2, -7x+5y=34.

3x+y=-2 ...1) -7x+5y=34 ...2) Using the substitution method: Rearrange equation 1): y=-3x-2 ...1)) substitute equation 1)) into eqaution 2) -7x +5(-3x-2)=34 -7x-15x-10=34 -22x=44 x=-2 subsitute x into 1)) y=...
SJ
Answered by Shaan J. Maths tutor
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