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What is solution by substitution?

Simultaneous equations - Solution by substitution As the variables (x & y) are the same in both equations , we can substitute from one equation into the other. This will give an equation with just one va...
AM
Answered by Antonia M. Maths tutor
7015 Views

When do I use the conditional perfect tense in a "si" clause?

The conditional perfect tense should be used in a "si" clause when there is no possibility for the event to happen. It must also be used with the pluperfect tense. For example: If I had known I wou...
DA
Answered by Daniel A. French tutor
4117 Views

Solve the following simultaneous equations: 4x + y = 14 and 6x - y = 16

First, write out the equations beneath each other: 4x + y = 14 6x - y = 16 Then, label the equations a and b (let's take the top one as a, and the bottom one as b) We always look to eliminate either the x te...
RS
Answered by Rebecca S. Maths tutor
8156 Views

Prove why the quadratic formula works

The quadratic formula is x = [- b ± √( b 2 - 4 ac )]/2 a (1) , where a,b and c are the coefficents of a quadratic in the form a x^2+ b x+ c =0 (2) . To prove that this works we need to start from equation (2...
JR
Answered by Jake R. Maths tutor
6852 Views

When should I use the passé simple?

The passé simple , or the 'past historic', is a very irregular past tense that is rarely used in spoken French. It indicates a highly literary style, and is therefore only heard in formal speeches, such as t...
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Answered by Rachael S. French tutor
11773 Views