What must be added to (2x - 3y) to get (x - 2y)?
5y - x
y - x
x - 5x
x - y
Correct answer is B
What must be added to 2x - 3y = Difference between x - 2y and 2x - 3y
x - 2y - 2y - (2x - 3y); x - 2y - 2x + 3y
= x - 2x + 3y - 2y
= y - x
Given that n(p) = 19, m(P \(\cup\) Q) = 38 and n(P \(\cap\) Q) = 7, Find n(C)
26
31
36
50
Correct answer is A
n(P \(\cup\) Q) = m(P \(\cap\) C)
38 = 19 = n(C) - 7
n(C) = 38 - 12
= 26
G varies directly as the square of H, If G is 4 when H is 3, find H when G = 100
15
25
75
225
Correct answer is A
G \(\alpha\) H2
G = KH2
4 = K(3)2
4 = 9k; K = \(\frac{4}{9}\)
100 = \(\frac{4}{9}H^2\)
4H2 = 900
H2 = \(\frac{900}{4}\)
H2 = 225
H = \(\sqrt{225}\)
H = 15
If \(\sqrt{72} + \sqrt{32} - 3 \sqrt{18} = x \sqrt{8}\), Find the value of x
1
\(\frac{3}{4}\)
\(\frac{1}{2}\)
\(\frac{1}{4}\)
Correct answer is C
\(\sqrt{2} + \sqrt{32} - 3\sqrt{18} = x\sqrt{8}\)
= \(\sqrt{36 \times 2} + \sqrt{16 \times 2} - 3\sqrt{2 \times 9}\)
= x\(\sqrt{2 \times 4}\)
= 6\(\sqrt{2} + 4\sqrt{2} - 9\sqrt{2} = 2 \times \sqrt{2}\)
\(\sqrt{2} (6 + 4 - 9) = 2x\sqrt{2}\)
\(\sqrt{2} = 2x \sqrt{2}\) divide both sides by \(\sqrt{2}\)
\(\frac{\sqrt{2}}{\sqrt{2}} = \frac{2 \times \sqrt{2}}{\sqrt{2}}\)
1 = 2x
2x = 1
x = \(\frac{1}{2}\)
Which of the following is not correct about the molecules of a substance in a gaseous state. They?
are in a constant state of motion
have different speeds
have a temperature which is measured by the average kinetic energy
The collision between the gases is perfectly inelastic
Correct answer is D
The collision between the gases is perfectly elastic