Question

Question #da2fb

Answer 1

`2. 9`
`4. 10`

Explanation:

I'll do questions `2` and `4`.

`2.` We need to factor the numbers within the square roots.

`=>5sqrt(4 xx 3) - 2sqrt(25 xx 3) + 3sqrt(9 xx 3)`

`=>5(2)sqrt(3) - 2(5)sqrt(3) + 3(3)sqrt(3)`

`=>10sqrt(3) - 10sqrt(3) + 9sqrt(3)`

`=>9sqrt(3)`

The numerical coefficient is `9`.

`4.` This is a trinomial factoring problem. When we want to factor a trinomial of the form `y = ax^2+bx + c, a!=1, 0`, we need to find two numbers that multiply to `ac` and that add to `b`.

`=>10r^2 - 8r + 35r - 28`

`=>2r(5r - 4) + 7(5r - 4)`

`=>(2r + 7)(5r - 4)`

The value of `a+ b + c + d` is `2 + 7 + 5 - 4 = 10`

Hopefully this helps!