Top answers

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

Multiply both sides by r: ra+3r = 2a + 7Move a to one side: ra -2a = 7-3rFactorise left hand side: a(r-2) = 7-3rMultiply both sides by (r-2): a= (7-3r) / (r-2)
TG
Answered by Tilly G. • Maths tutor
4375 Views

Solve 5x^2 = 10x + 4 Give your answers to 2 decimal places. [4 marks]

5x^2 = 10x + 4 5x^2 - 10x = 4 5x^2 - 10x - 4 = 0 ax^2 +bx +c = 0 x = (-b (+/-) ( b 2 -4ac) 1/2 ) /(2a) x = (--10 (+/-) ((-10) 2 - (4 x 5 x -4)) 1/2 )/(2 x 5) x = (10 (+/-) (100 + 80) 1/2 )/10 x = (10 (+/-) (...
JT
Answered by JOSHUA T S. • Maths tutor
7299 Views

work out the area of a trapezium where the height is 4mm, the top length is 8mm and the bottom length is 12.5mm

the formula for area of a trapezium = 0.5(a+b)htherefore, a = 8, b = 12.5, h = 4therefore, the total area would be 41mm squared
RP
Answered by Rianna P. • Maths tutor
3409 Views

Factorise the following equation: x^2 + x - 6

Answer: (x+3)(x-2)
EN
Answered by Eli N. • Maths tutor
3181 Views

Simplify (x+4)^(2)-(x-2)^(2)

Treat the question, (x+4) 2 -(x-2) 2 as a 2 -b 2 where we can simplify as (a+b)(a-b). ie. (x+4+x-2)(x+4-x+2) *be careful about change of signsWe then get (2x+2)(6) which expands to 12x+12 and we can then sim...
LT
Answered by Loreen T. • Maths tutor
4249 Views