If x + y = 2y - x + 1 = 5, find the value of x
3
2
1
-1
Correct answer is B
x + y = 2y - x + 1 = 5
x + y = 2y - x + 1
x + x + y - 2y = 1
2x - y = 1....(i)
2y - x + 1 = 5
-x + 2y = 5 + 1
-x = 2y = 4
x - 2y = -4 .....(ii)
solve simultaneously (i) x 2x - y = 1
(ii) x x - 2y = -4
2x - y = 1
=2x - 4y = -8
3y = 9
y = \(\frac{9}{3}\)
y = 3
substitute y = 3 into equation (i)
2x - y = 1
2x - 3 = 1
2x = 1 + 3
2x = 4
x = \(\frac{4}{2}\)
= 2
Make p the subject of the relation: q = \(\frac{3p}{r} + \frac{s}{2}\)
p = \(\frac{2q - rs}{6}\)
p = 2qr - sr - 3
p = \(\frac{2qr - s}{6}\)
p = \(\frac{2qr - rs}{6}\)
Correct answer is D
q = \(\frac{3p}{r} + \frac{s}{2}\)
q = \(\frac{6p + rs}{2r}\)
6p + rs = 2qr
6p = 2qr - rs
p = \(\frac{2qr - rs}{6}\)
Simplify: \(\frac{54k^2 - 6}{3k + 1}\)
6(1 - 3k2)
6(3k2 - 1)
6(3k - 1)
6(1 - 3k)
Correct answer is C
\(\frac{54k^2 - 6}{3k + 1} = \frac{6(9k^2 - 1)}{3k + 1}\)
= \(\frac{6(3k + 1) - (3k - 1)}{3k + 1}\)
= 6(3k - 1)
Solve for x in the equation; \(\frac{1}{x} + \frac{2}{3x} = \frac{1}{3}\)
5
4
3
1
Correct answer is A
\(\frac{1}{8} + \frac{2}{3x} = \frac{1}{3}\)
= \(\frac{1}{2}\)
\(\frac{5}{3x} = \frac{1}{3}\)
3x = 15
x = \(\frac{15}{3}\)
= 5
5%
7\(\frac{1}{2}\)%
8%
10%
Correct answer is D
A = 3,500, P = N2,500
A = P + I
But I = N3,500 - N2,500
I = N1,000
I = \(\frac{PRT}{100}\)
N1,000 = \(\frac{2.500 \times R \times 4}{100}\)
1000 = 100R
R = \(\frac{1000}{100}\)
= 10%