Hey, today I switched off in class.
I need some serious help with my homework even if it is like a couple of questions please help! (Yes it is basic mathematics)
Our teacher said use BIDMAS,

Quote:

1.Tina said, “When x = 3, then the value of 4x2 is 144”.
Bryan said, “When x = 3, then the value of 4x2 is 36”.
(a) Who was right? Explain why.
(b) Work out the value of 4(x + 1)2 when x = 3.
2. D = ut + kt2
u = 20
t = 1.2
k = –5
Work out the value of D.
3. Find the value of t2 – 4t when t = 34. P = x2 7x. Work out the value of P when x = 5.

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5. Alex has a mobile phone.
Each month he pays
13.4p for each minute he uses his mobile phone
and
a fixed charge of £18.75
In January Alex uses his mobile phone for 405 minutes. Work out the total amount Alex pays.

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6. Sophie says, ‘For any whole number, n, the value of 6n – 1 is always a prime number’.
Sophie is wrong.
Give an example to show that Sophie is wrong.

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7. P = 2x2 + 3 Find the value of P when x = –5.

1.Tina said, “When x = 3, then the value of 4x2 is 144”.
Bryan said, “When x = 3, then the value of 4x2 is 36”.
(a) Who was right? Explain why.
(b) Work out the value of 4(x + 1)2 when x = 3.
2. D = ut + kt2
u = 20
t = 1.2
k = –5
Work out the value of D.
3. Find the value of t2 – 4t when t = 34. P = x2 7x. Work out the value of P when x = 5.

1. a) The equation is 4x2.
This shows you are multiplying the 4 by the x and then by the 2.
Sub 3 into the x
It becomes 4(3)2 which equals 24.

a) He meant 4x^2 for the first problem, and Bryan would be correct. Seeing as PEMDAS states that you do exponents before multiplying; therefore, it would be 4(9). Which obviously equal 36.