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Solve the simultaneous equations: y = 4x^2 - 9x - 1 and y = 5 - 4x

Subtract the second equation from the first, giving you: 4x^2 -5x -6 Factorise the quadratic: (4x + 3)(x - 2) x = -0.75 x= 2 Now substitute these values into one of the equations (or both, just to double-che...
DA
Answered by Damilola A. • Maths tutor
10627 Views

Why is it not '我是好'? In basic adjectival sentences, why is the copula verb 'to be' not used?

Take the simple sentence 'I am good' - 'I' is the subject, 'am' is the first-person of the verb 'to be', and 'good' is the adjective.In English, the verb 'to be' is needed in adjectival sentences to link the...
KY
Answered by Kwan Yee L. • Mandarin tutor
8137 Views

How do we differentiate y=a^x when 'a' is an non zero real number

Firstly we must change it into a form we can deal with. To do this we take the natural log (ln) of both sides.ln(y)=ln(a x ) ln(y)=x(ln(a)) using our rules of logsFrom here we differentiate. The differential...
MJ
Answered by Marcus J. • Maths tutor
8479 Views

If (m+8)(x^2)+m=7-8x has two real roots show that (m+9)(m-8)<0 where m is an arbitrary constant

For this we are going to test our knowledge of discriminats and factorisation. Firstly we will format the equation as (m+8)x 2 +8x+(m-7)=0From here we can see it takes the form ax 2 +bx+c, and as we know the...
MJ
Answered by Marcus J. • Maths tutor
5389 Views

What are cases?

Every word has a function in a sentence. Sometimes, we can take words away and the sentence still makes sense. However, at other times, some words are essential for the sentence to not sound 'odd.' Say the s...
ML
Answered by Marcus L. • German tutor
4835 Views