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Expand and simplify (2x+5)(x^2 + 3x -1)

The answer should be 2x³ + 11x²+13x - 5

Remeber to multipy both brackets together, and collect like terms. (Watch out for the minus sign)

Answered by Fraser P. • Maths tutor

4288 Views

y=2x+5 and y-x=8. Find x and y.

The expression (2x+5) has the same value as y, and so we can use (2x+5) instead of y in the second equation. This means that we are now just dealing with one variable (x) instead of two (x and y). If we m...

Answered by Smriti R. • Maths tutor

10877 Views

Find the length of a side of the triangle (Pythagoras' Theorem) Two sides are of length 3cm and 4cm, find the length of the Hypotenuse.

a²= 3²= 9, b²= 4²= 16, a²+ b² = 3² + 4² = 25, c² = 25, c = 5

Answered by Andrew D. • Maths tutor

2738 Views

There are 892 litres of oil in Mr Aston’s oil tank. He uses 18.7 litres of oil each day. Estimate the number of days it will take him to use all the oil in the tank.

Estimate, so: 900 litres, and 20 litres per day. 900/20 = 45 However, any estimation that results in an answer between 44-56 is acceptable.

Answered by Christopher L. • Maths tutor

8870 Views

Rearrange "(6y-30)/5 = 2x+(12/5)" so it reads "y = ... ". Sketch this line and label where it meets the axes.

multiply everything by 5, so you get 6y - 30 = 10x + 12 - add 30 to both sides, so you get 6y = 10x + 42 - divide everything by 6, so you have y = (10/6)x + (42/6) - simplify, y= (5/3)x + 7 - this i...

Answered by Tegan H. • Maths tutor

3008 Views