Top answers

The equation 5x^2 + px + q = 0, where p and q are constants, has roots t and t+4. Show that p^2 = 20q + 400.

We know that if we have a polinomial of the form ax^2 + bx + c = 0, then:sum of the roots = -b/a and product of the roots = c/a Therefore: t + (t + 4) = -p/5 and t(t + 4) = q/5 Therefore: 2t + 4 = -p/5 so t ...
AB
Answered by Alexandra B. • Maths tutor
5083 Views

Solve the simultaneous equations: 3x+5y=19, 4x-2y=-18

For all simultaneous equations it is useful to number each one to keep your working clear and concise. In order to solve this we need to eliminate one of the variables (x or y) by manipulating the equations....
BW
Answered by Ben W. • Maths tutor
9985 Views

If 5x + 3y = 27 and 6x - 2y = 10, find x and y

5x + 3y = 27 (1)6x - 2y = 10 (2)Rearrange (1) to make x the subject.Subtracting - 3y from both sides gives5x = 27 - 3yDivide both sides by 5 givesx = (27 - 3y)/5Substitute (1) into (2) gives6(27 - 3y)/5 - 2y...
TA
Answered by Thomas A. • Maths tutor
3922 Views

What is the balance of payments?

Current accountThe balance of payments plus net investment incomes from overseas assets and net transfersBalance of trade in goods: the difference between imports and exports of goods in the primary and seco...
AT
Answered by Arron T. • Economics tutor
2644 Views

How do I plot a graph of y=x^3-9x?

To begin with we see that y=x 3 -9x is a positive cubic function, and therefore we know its general shape.The first step is to find the x interecepts. We do this by setting y=0 and solving the resulting equa...
TD
Answered by Tutor127548 D. • Maths tutor
8998 Views