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Triangle ABC has perimeter 20 cm. AB = 7 cm. BC = 4 cm. By calculation, deduce whether triangle ABC is a right-angled triangle. 4 marks.

We know that the perimeter of the triangle is 20cm and we also know the value of two of the sides of the triangle, AB=7cm and BC=4cm. We can work out the length of the third side (AC) by subtracting the k...

Answered by Charlotte M. • Maths tutor

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If x:y = 7:4 and x+y = 88 , work out the value of x–y.

We know that x:y is 7:4, and therefore x is seven-elevenths of the total value of x and y. Therefore we can express x = 7/11 (x+y). Since we also know that the total of x+y is 88, we can substitute this i...

Answered by Reece S. • Maths tutor

10883 Views

Compare the following logarithms in base 1/2 without a calculator: log(8) and log(512)

Compare through subtraction : log_0.5(8)- log_0.5(512) = xUsing logarithm rule in addition/subtraction: log_a (b)+log_a(c) = log_a(b*c) ; log_a

Answered by Gael A. • Maths tutor

2729 Views

y=7-2x^5. What's dy/dx?Find an equation for the tangent to the curve where x=1. Is itan increasing or decreasing function when x=-2?

dy/dx=-10x^4When x-1, gradient =-10 Tangent is then: y+10x=15When x=-2, dy/dx=-160 so a decreasing function

Answered by Khai L. • Maths tutor

3970 Views

Factorise the following: 21x(squared)-35x

The question is asking us to factorise, this means put the equation into a simplified bracket. The first step is to find the highest common factor (HCF), the HCF must be a factor of 21x² as wel...

Answered by Annesa M. • Maths tutor

4006 Views