1. The sides of a triangle are 16 cm, 30 cm, 34 cm. Its area is (a) 225 cm sq. (b) 225root3 cm (c) 225root2 cm
(d) 450 cm sq.

240 cm^2,

Step-by-step explanation:

Use Hero's formula:

Area = √(s(s-a)(s-b(s-c))  where s = the semi-perimeter and a, b  and c are the lengths of the 3 sides.

s = (16+30+34)/2 = 80/2 = 40

So the area = √(40(40-16)(40-30)40-34))

= √(40*24*10*6)

=  √57600

= 240.

option 3 . (5x + 1) - (-10x + 6)

step-by-step explanation:

option 1 :

(4x + 3) + (-9x + 4)

or 4x+3 -9x + 4

or -5x + 7

option 2

(x - 2) - (6x - 9)

or x-2-6x + 9

or -5x + 7

option 3

(5x+ + 6)

or 5x + 1 + 10x -6

or 15x -5

option 4

-4x+2x+7-3x

-7x + 2x + 7

-5x + 7

hence only option 3 did   not satisfy the given simplify expression.