(2a-3b) (2a+3b)
(2a-b) (2a+3b)
(2a-3b) (a+3b)
(a-3b) (a+3b)
Correct answer is A
Check:
(2a-3b) (2a+3b)
4a\(^2\) + 6ab - 6ab - 9b\(^2\)
4a\(^2\) - 9b\(^2\)
Find x if the mean of 2x, 4x, 2x - 13 and 6x is 4.
1.5
2.0
1.0
0.5
Correct answer is B
mean (4) = \(\frac{2x + 4x + 2x - 13 + 6x}{4}\)
16 = 14x - 13
16 + 13 = 14x
x = 29/14 or 2.07
If 8, p, q and 26 is an A.P. Find the values of p and q
p = 14 and q = 14
p = 20 and q = 14
p = 20 and q = 20
p = 14 and q = 20
Correct answer is D
The common difference is 6. Just add 6 to get the next term 8, 14, 20 and 26
If y varies inversely as x and x = 3 when y =4. Find the value of x when y = 12
4
1
2
3
Correct answer is B
y = 1/x; y = \(\frac{k}{x}\)
k =xy → 3 * 4 = 12
x = \(\frac{k}{y}\)
x = \(\frac{12}{12}\) = 1
223
232
32
-232
Correct answer is A
3 * 5 = 3 - 5 + (3 x 5)\(^2\)
-2 + (15)\(^2\)
-2 + 225
= 223