Factorise completely a) ( 2 + 2 + 2) a) 9a(x – 3b ) - 4 (x – 3b)
b) 5a(2b – 3 ) - 4 (2b – 3)
c) x( 2h-k )+ 3y ( k – 2h )

a) (9a-4)(x-3b)

b) (5a-4)(2b-3)

c) (x-3y)(2h-k)

Step-by-step explanation:

9a(x – 3b ) - 4 (x – 3b) = (9a-4)(x-3b)

Since both 9a and -4 are multiplied by (x-3b), they can be put in a bracket too.

5a(2b – 3 ) - 4 (2b – 3) = (5a-4)(2b-3)

Since both 5a and -4 are multiplied by (2b-3), they can be put in a bracket too.

x( 2h-k )+ 3y ( k – 2h ) = x(2h-k) - 3y (-k + 2h)

We can multiply + 3y ( k – 2h ) by (-1) to switch up the arithmetic operations.

x(2h-k) - 3y (-k + 2h) = x(2h-k) -3y(2h-k)

Since both x and -3y are multiplied by (2h-k), they can be put in a bracket too.

x(2h-k) -3y(2h-k) = (x-3y)(2h-k)

d. millimeters per hour.

step-by-step explanation:

we are given that,

carlo used a rain gauge to measure the amount of water his lawn is receiving from the sprinklers.

since, according to the options, we see that,

water cannot be measured by 'miles per hour', 'meters per second' and 'grams per seconds'.

we get that, the water can be measured by 'millimeters per hour'.

hence, the appropriate rate for describing the amount of water is 'millimeters per hour'.

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