Question

Pls help me by answering these :(

Answer 1

1) 21

2a) -23/30

2b) 6/55

Explanation:

1) 3(x + 2) + 5x + 7

expand the brackets:

= 3x + 6 + 5x + 7

collect like terms:

= 8x + 13

when x = 1, (just substitute 1 for x)

8(1) + 13

= 8 + 13

= 21

2a)

-9/10 + 2/15

put both fractions on the same denominator (often we can just multiply each denominator by the other one):

so -9/10 * 15/15

= -135/150

and 2/15 * 10/10

= 20/150

now they're both on the same denominator and we can add the numerators:

-135 + 20 = -115

so our answer is:

-115/150

which we can simplify to:

-23/30

2b)

3/11*2/5

Multiplying fractions is very simple, as it doesn't require to have the same denominators. We can just multiply the numerators by each other and same for the denominators:

3*2 = 6

11*5 = 55

therefore, our answer is:

6/55

Answer 2

A)

3(x+2) + 5x + 7

3x + 6 + 5x + 7

3x + 5x + 6 + 7

put x = 1

3(1) + 5(1) + 6 + 7

3 + 5 + 6 + 7

21

B)

a)

`\sf \rightarrow -(9)/(10) + (2)/(15)`

`\sf \rightarrow -(9(15))/(150) + (2(10))/(150)`

`\sf \rightarrow -(135)/(150) + (20)/(150)`

`\sf \rightarrow (-135+20)/(150)`

`\sf \rightarrow (-115)/(150)`

`\sf \rightarrow (-23)/(30)`

b)

`\sf \rightarrow (3)/(11) \ * \ (2)/(5)`

`\sf \rightarrow (3*2)/(11 *5)`

`\sf \rightarrow (6)/(55)`