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Solve the simultaneous equations (1) 2a - 5b = 11 (2) 3a + 2b = 7

(1)x2 4a - 10b = 22(2)x5 15a + 10b = 35(1) + (2) 19a = 57a = 3sub a = 3 into (1)2(3) - 5b = 116 - 5b = 11-5b = 55b = -5b = -1
HC
Answered by Hannah C. • Maths tutor
9639 Views

A picture is bought at a sale for £40. It is laster sold for £50. What is the percentage profit?

percentage profit = percentage increasepercentage increase = (difference/original) x 100 = (50 - 40)/40) x100=25%
HC
Answered by Hannah C. • Maths tutor
6846 Views

Solve the simultaneous equations: 4x+3y=5 and x-y=3, to find the values of x and y.

First of all, we need to get the equations in a form so that either x or y can be eliminated. In this case, I have a positive amount of y, and a negative amount of y, meaning that I can add the two equations...
LP
Answered by Laura P. • Maths tutor
11941 Views

If Lisa loses 23% of £650, how much has she lost?

Percentages are always out of 100 - imagine the fraction 1/100. If I asked you to work out 1/100 of a number, how would you do it?It's pretty much the same for percentages - because 1% is the same as 1/100. ...
EA
Answered by Ewaola A. • Maths tutor
4103 Views

Find f'(x) and f''(x) when f(x) = 3x^2 +7x - 3

We know that when f(x) = x^n, f'(x) = nx^n-1 (1) So we apply this to all components of f(x), giving f'(x) = 2(3x) + 7 = 6x +7 to find f''(x), we apply (1) to f'(x). Giving f''(x) = 6
GP
Answered by Georgiana P. • Maths tutor
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