Question

3. x varies directly as y2. Given that for y = 3, x = 2. The value of x when y = 5 will
be
5
18
(b) 59
(c)
(d)
12
25
(a) 5
9
25​

Answer 1

Step-by-step explanation:

x varies directly as y

2

. Given that for y=3,x=2. What is the value of x when y=5?

Q2

Simplify

(i) (x

2

−5)(x+5)+25

(ii) (a

2

+5)(b

3

+3)+5

(iii) (t+8

2

)(t

2

−s)

(iv) (a+b)(c−d)+(a−b)(c+d)+2(ac+bd)

(v) (x+y)(2x+y)+(x+2y)(x−y)

(vi) (x+y)(x

2

−xy+y

2

)

(vii) (1.5x−4y)(1.5x+4y+3)−4.5x+12y

(viii) (a+b+c)(a+b−c)

Q3

If y varies jointly as a and b and inversely as the square root of c, and y=12 when a=3,b=2, and c=64, find y when a=5,b=2, and c=25.