Top answers

A straight line passes through the points (-2, 4) and (1, 10). What is (a) the gradient of the line, (b) the y-intercept of the line and (c) the equation of the line?

(a) Gradient (m) = (y 2 -y 1 )/(x 2 -x 1 ) = (10-4)/(1-(-2)) = 6/3 = 2 (b) General equation of a straight line: y = mx + c (c = y-intercept) For our straight line: y = 2x + c Test points: 4 = 2(-2) + c ---&g...
SB
Answered by Samuel B. • Maths tutor
14620 Views

Factorise the equation x^2 +5x = 6

On first glance, this looks like it is going to be a quadratic equation, so let’s try and put it in the form ax 2 + bx + c = 0 which we can factorize. If we subtract 6 from each side, we end up with x 2 +5x ...
MJ
Answered by Matthew J. • Maths tutor
9384 Views

The area of a rectangle is 8cm^2. The rectangle is (3x+1) by (2x+5). Find the value of x

Area of a rectangle is width times height (3x+1)(2x+5)= 6x 2 +15x+2x+5 6x 2 +17x+5 Set formula of area equal to known area value. 6x 2 +17x+5= 8 6x 2 +17x-3 = 0 (6x-1)(x+3)=0 (or use quadratic formula) x=-3 ...
CD
Answered by Conrad D. • Maths tutor
6638 Views

Find the inverse of the following function: g(x) = 4/(3-x)

A function is simply a process that takes in a number, does a few operations on it (for example, add, multiply etc), and then gives out another number. If you want to figure out the inverse of a function, al...
EM
Answered by Eytan M. • Maths tutor
5662 Views

How do you complete the square?

Say you start with a general equation of x 2 +ax+b=0. (If the x 2 has a coefficient the you will need to divide by that first.) You need to move to the equation (x+a/2) 2 -(a/2) 2 +b=0. Then put all of the c...
BC
Answered by Bryony C. • Maths tutor
3375 Views