Page 163 - ICSE Math 8

(c) If a given algebraic expression is the _________ of two squares, then it can be factorized by using
2
2
the identity p – q = (p + q)(p – q).
(d) The factors of _________ are (a + 2) and (a – 6).
2
(e) 2x + 6y – 3(x + 3y) when factorized gives (x + 3y)_________.

PRACTICE TIME

1. Factorize the following.
3
2
2 2
3 5
4 4
4
2 5
(a) 9x y – 27xy (b) 2x y – 3x y + 4x y (c) y (p + 2q) + y (p + 2q)
2
4
2
(d) x – 16 (e) y + ay + by + ab (f) (x – y) – (x + y) 2
2
4
3 2
(g) 16 – 24y + 9y 2 (h) 75x y – 108xy 4 (i) y + y + 1
2
2
2
2
2
(j) x + 6x – 16 (k) (x + 4x) – 5(x + 4x) – y(x + 4x) + 5y
2. You want to construct a frame for a rectangular photo. The width of the x
frame should be the same all the way around and the total area of the frame 17 in. 11 in.
and photo should be 315 sq. in. What should be the outer dimensions of the x
frame? x
THINK SMART
1. The length of a rectangle is 8 more than its breadth. The area of rectangle is 240 sq. m. Write an equation
for its area assuming the breadth to be ‘b’. Also, solve the equation to find the length and breadth.
3p 7 2 3 7 2
2. Verify: + – p + = 2
7 6p 7 6p

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