The two top questions

1a. x=1/2              1b. x= 4

Step-by-step explanation:

1a. 30x= 16- 2x

(add 2x to both sides)

32x= 16

(divide both sides by 16)

x= 1/2

1b. 2(3x-5)=2x+6

(distribute the 2)

6x-10=2x+6

(add 10 to both sides)

6x=2x + 16

(subtract 2x from both sides)

4x= 16

(divide both sides by 4)

x=4

- 2 + 10x³ - 21x² + 19x - 4

step-by-step explanation:

each term in the second factor is multiplied by each term in the first factor

x²(- 2x² + 4x - 1) - 3x(- 2x² + 4x - 1) + 4(- 2x² + 4x - 1) ← distribute

= - 2 + 4x³ - x² + 6x³ - 12x² + 3x -8x² + 16x - 4

collect like terms

= - 2 + 10x³ - 21x² + 19x - 4 ← in standard form

13

step-by-step explanation:

divide the cost of the total of sodas you bought by the cost of one soda, for example:

$24.57 divided by $1.89 is 13 which means you bought 13 sodas