Solve for x and y respectively
3x - 5y = 9
6x - 4y = 12
\(\frac{3}{4}\), 1
\(\frac{4}{3}\), 1
\(\frac{3}{4}\), -1
\(\frac{4}{3}\), -1
Correct answer is D
3x - 5y = 9 ------x2
6x - 4y = 12 -----x1
6x - 10y = 18
-6x - 4y = 12
____________
\(\frac{6y}{-6}\) = \(\frac{6}{6}\)
y = -1
in eq (1) 3x - 5y = 9
3x - 5(-1) = 9
3x + 5 = 9
3x = 4
x = \(\frac{4}{3}\)
If N = \(\frac{p}{2}\)(\(\frac{T_1 - T_2}{T_1}\)). Find P when N = 12, T1 = 27 and T2 = 24.
48
108
54
216
Correct answer is D
N = \(\frac{p}{2}\)(\(\frac{T_1 - T_2}{T_1}\))
12 = \(\frac{p}{2}\)(\(\frac{27 - 24}{27}\))
24 = P(\(frac{3}{27}\)
P = 24 x 9 = 216
Evaluate \(\int\)(sinx - 5x2)dx
-cosx - 10x + k
cosx - \(\frac{5x^3}{3}\) + k
-cosx - \(\frac{5x^3}{3}\) + k
cosx - 10x + k
Correct answer is C
\(\int\)(sin x - 5x^2) = -cosx - \(\frac{5x^3}{3}\) + k
Find \(\frac{dy}{dx}\). If y = 3x3 + 2x2 + 3x + 1
9x2 + 4x + 3
9x2 - 4x - 3
9x2 + 4x - 3
9x2 - 4x + 3
Correct answer is A
y = 3x3 + 2x2 + 3x + 1
\(\frac{dy}{dx}\) = 9x2 + 4x + 3
If a car travels 120km on 45 litres of petrol, how much petrol is needed for a journey of 600km?
720 litres
160 litres
225 litres
960 litres
Correct answer is C
120km \(\to\) 45litres
1km \(\to\) \(\frac{45}{120}\)litres
600km \(\to\) \(\frac{45}{120}\) x 600 = 225litres