Given that x2 + y2 + z2 = 194, calculate z if x = 7 and \(\sqrt{y}\) = 3
\(\sqrt{10}\)
8
12.2
13.4
Correct answer is B
Given that x2 + y2 + z2 = 194, calculate z if x = 7 and \(\sqrt{y}\) = 3
x = 7
∴ x2 = 49
\(\sqrt{y}\) = 3
∴ y2 = 81 = x2 + y2 + z2 = 194
49 + 81 + z2 = 194
130 + z2 = 194
z2 = 194 - 130
= 64
z = \(\sqrt{64}\)
= 8
Simplify \(\frac{x}{x + y}\) + \(\frac{y}{x - y}\) - \(\frac{x^2}{x^2 - y^2}\)
\(\frac{x}{x^2 - y^2}\)
\(\frac{y^2}{x^2 - y^2}\)
\(\frac{x^2}{x^2 - y^2}\)
\(\frac{y}{x^2 - y^2}\)
Correct answer is B
\(\frac{x}{x + y}\) + \(\frac{y}{x - y}\) - \(\frac{x^2}{x^2 - y^2}\)
\(\frac{x}{x + y}\) + \(\frac{y}{x - y}\) - \(\frac{x^2}{(x + y)(x - y}\)
= \(\frac{x(x - y) + y(x + y) - x^2}{(x + y)(x - y}\)
= \(\frac{x^2 + xy + xy + y^2 - x^2}{(x + y)(x - y}\)
= \(\frac{y^2}{(x + y)(x - y)}\)
= \(\frac{y^2}{(x^2 - y^2)}\)
N32.00
N320.00
N420.00
N1680.00
Correct answer is B
Let his assistant work for x days
∴ his master worked (x + 10) day. Amount received by master = 40(x + 10),
amount got by his assistance = 10x
Total amount collected = N2000.00
∴ 40(x + 10) + 10x = 2000
= 40x + 400 + 10x
= 2000
50x + 400 = 2000
50x = 2000 - 400
50x = 1600
x = \(\frac{1600}{50}\)
x = 32 days
The perimeter of a rectangular lawn is 24m. If the area of the lawn is 35m2; how wide is the lawn?
5cm
7m
12m
14m
Correct answer is A
No explanation has been provided for this answer.
Find the solution of the equation x - 8\(\sqrt{x}\) + 15 = 0
3, 5
-3, -5
9, 25
-9, 25
Correct answer is C
x - 8\(\sqrt{x}\) + 15 = 0
x + 15 = 8\(\sqrt{x}\)
square both sides = (x + 15)2 = (8 \(\sqrt{x}\)2
x2 + 225 + 30x = 64x
x2 + 225 + 30x - 64x = 0
x2 - 34x + 225 = 0
(x - 9)(x - 25) = 0
x = 9 or 25