Top answers

Solve x^2+4x-5=0 by completing the square.

x^2+4x-5=0(x+2)^2-(2)^2-5=0subtract 2^2 as (x+2)^2 = x^2+4x+4 when we want x^2+4x(x+2)^2-4-5=0(x+2)^2-9=0(x+2)^2=9square root both sidesx+2=+/-3x=-2+/-3x=-2+3 or x=-2-3x=1 or x=-5
EM
Answered by Evie M. • Maths tutor
10992 Views

The radius of a pizza is 12cm, calculate the area of the pizza in terms of pi

To calculate the answer to this question we need to know the formula for the area of the circle. The area of a circle is: A = Pi x r^2 The value of r is given in the question; r = 12. We then just plug this ...
BB
Answered by Beth B. • Maths tutor
9647 Views

Find the area under the curve y = (4x^3) + (9x^2) - 2x + 7 between x=0 and x=2

To be able to solve this, the equation needs to be integrated. To do this, simple integration needs to be applied where the power of 'x' increases by 1 and the coefficient of 'x' is divided by the new power....
YS
Answered by Yash S. • Maths tutor
5430 Views

GCSE 2011: Solve the simultaneous equations: y^2 = 2x + 29 and y = x - 3

This was the final question in AQA's 2011 non-calculator paper, and most top candidates will be looking to score all 5 marks that are on offer. Our usual technique for simultaneous equations isn't going to w...
RG
Answered by Ross G. • Maths tutor
8394 Views

The circle c has equation x^2+ y^2 = 1. The line l has gradient 3 and intercepts the y axis at the point (0, 1). c and l intersect at two points. Find the co-ordinates of these points.

x^2 + y^2 =1 y = 3x + 1 x^2 + (3x + 1)^2 = 1 x^2 + 9x^2 + 6x+ 1 = 1 10x^2 + 6x = 0 x(10x+6) = 0 x= 0 or x = -6/10 = -3/5 When x = 0, y = 1 When x = -3/5, y = -4/5
PJ
Answered by Prince J. • Maths tutor
4416 Views