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how to solve a quadratic inequality

in the case you have ax²+bx+c>n where a,b,c and n are all real integers (non fractions, ration numbers that can be +ve or -ve) use the quadratic formula [-b+/-(b²-(4c))^1/2

Answered by J B. • Maths tutor

2779 Views

A is (2, 12) and B is (8, 2) Calculate the midpoint of AB.

Find the difference between the x co-ordinates and divide by two, apply the same principle to the y co-ordinates
Answer: (5,7)

Answered by Ashan D. • Maths tutor

7238 Views

Solve the simultaneous equations: 6x + 3y = 42 4x + 7y = 38

6x + 3y = 42 => y = 14 - 2x (1 method mark)4x + 7y = 38 (substituting in y) => (1 method mark) 4x + 7(14 - 2x) = 384x + 98 - 14x = 38-10x + 98 = 3860 = 10x => x = 6 (1 answer mark) => y = 14 -...

Answered by Daniel T. • Maths tutor

3704 Views

It is given that z = 3i(7-i)(i+1). Show that z can be written in the form 24i - k. State the integer k.

z = 3i(7-i)(i+1)= 3i(7i-i+7-i²)= 3i(6i+8)= 18i²+24 (1 method mark)= 24i-18 (1 method mark)k=18 (1 answer mark)

Answered by Daniel T. • Further Mathematics tutor

2195 Views

What are surds and how do I use them ?

Surds are irrational numbers, (numbers which cannot be expressed as fractions), and normally shown as a number instead a square root, but the number itself isn't a square. For example root 3 is a surd, wh...

Answered by Roly H. • Maths tutor

6190 Views