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What is the solution to the system of equations defined by (1) x+2y = 4 and (2) y+2x = 6?

We rearrange equation (1) to obtain an expression in terms of x. We then substitute this expression in place of x in equation (2), rearranging to find the numerical value of y. This value of y can then be su...
JH
Answered by Jake H. • Maths tutor
3830 Views

x^2 - x - 90 = 0. Solve to find x.

Comparing to this to ax^2 + bx + c = 0, you'll find that a=1, b=-1, c=90. You need to split b (in this case -1), into two numbers that add up to b (-1), and multiply to ac (90). -> These are -10 and 9. No...
YL
Answered by Yanakan L. • Maths tutor
4494 Views

There are 30 balls in the bag, 10 of which are blue. Adam takes 2 balls out of the bag without a replacement and calculated that there is a probability of 0.2 of both balls being blue. What percentage error did he make compared to the true probability?

True probability of 2 consecutive balls picked being blue: (10/30)*(9/29)=3/29 which is 0.1034 (4 d.p.) 3/29-100% 0.2-x% so, x=0.2*100/(3/29)= 193.3 (1 d.p.) therefore Adam's result is 93.3 % (1 d.p.) over t...
DK
Answered by Deimena K. • Maths tutor
3825 Views

Solve 7x=4(x-8)

The first thing you need to do to make this easier is to multiply out the brackets so that you can then move all the 'x' terms to one side and all the numbers to the other side. It would become: 7x=4x-32 You...
MU
Answered by Megha U. • Maths tutor
5860 Views

How do you find the HCF of 110 and 132

Draw a diagram breaking down 110 and 132 into their multiples (on whiteboard), e.g. 110=11 10 132=11 12 Circle the prime numbers, 11, and then break down the composite numbers (those that aren't prime) into ...
JJ
Answered by Josiah J. • Maths tutor
18918 Views