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A triangle has sides A, B and C. The side BC has length 20cm, the angle ABC is 50 deg and angle BAC is 68 deg. a) Show that the length of AC is 16.5cm, correct to three significant figures. b) The midpoint of BC is M, hence find the length of AM

a) The answer to this question is quite simple, it is all dependent on the pupil realising that they need to use the sine rule. This rule for this triangle is: BC/sin(BAC) = AC/sin(ABC) Once they get this eq...
RS
Answered by Ravi S. • Maths tutor
5898 Views

How do I find the inverse of a 2x2 matrix?

Hiya! So the very first thing we need to do is find the determinant, which is just a fancy word to describe a matrix; for a 2x2 matrix, it's equal to "ad-bc", where: (a b c d) This will give you a ...
NC
Answered by Namir C. • Maths tutor
6187 Views

There are 40 pencils in a box. There are 15 pens in a packet. John gives one pencil and one pen to each person at a conference. He has no pencils or pens left. How many boxes of pencils and how many packets of pens did John buy?

Multiples of 15: 15, 30, 45, 60, 75, 90, 105, 120 Mulitples of 40: 40, 80, 120 This means that there are 120 people at the conference, and that he sold 3 boxes of pencils (40x3=120) and 8 boxes of pens (15x8...
AP
Answered by Anastasia P. • Maths tutor
24599 Views

What is the solution to the system of equations defined by (1) x+2y = 4 and (2) y+2x = 6?

We rearrange equation (1) to obtain an expression in terms of x. We then substitute this expression in place of x in equation (2), rearranging to find the numerical value of y. This value of y can then be su...
JH
Answered by Jake H. • Maths tutor
3847 Views

What is the value of the integral of e^x from x = 1 to x = 2?

As the derivative of e^x is e^x, so is the integral (plus some constant). As we wish to find the value of the integral from x = 1 to x = 2, we substitute x=2 into e^x, and from that we subtract e^x with x=1....
JH
Answered by Jake H. • Maths tutor
4693 Views