PLEASE HELP I WILL MARK YOU BRAINLIEST determine the exact and approximat solutions for 4(x + 5)^2 = 21 show your steps

x = − 5 + 1/2 √ 21 or x = − 5 + − 1/2 √ 21

Step-by-step explanation:

Let's solve your equation step-by-step.

4(x+5)^2=21

Step 1: Simplify both sides of the equation.

4x^2+40x+100=21

Step 2: Subtract 21 from both sides.

4x^2+40x+100−21 =21−21 4x^2+40x+79=0

For this equation: a=4, b=40, c=79

4x^2+40x+79=0

Step 3: Use quadratic formula with a=4, b=40, c=79.

x= −b±√ b^2−4ac/2ax

= −(40)+√ (40)^2−4(4)(79)/2(4)

x = 40^2±√ 336/8

x= −5+1/2 √ 21 or x = −5+ − 1/2√ 21

x = − 5 + 1/2 √ 21 or x = − 5 + − 1/2 √ 21

( I hope this was helpful) >;D

linearly: 8560 bacteria

exponentially: approximately 75233 bacteria

step-by-step explanation:

assuming it is not exponential (we would have some really complicated logarithms), let's say it is linear. then, after 5 hours, it increased by 1200 bacteria, so every hour it increases by 240 bacteria. this means that after 19 hours, we get 19 * 240 + 4000 bacteria or 3800 + 760 + 4000 = 7800 + 760 = 8560 bacteria.

because it says round your answer, i will do this exponentially (with a calculator, of course). first, we need to find how much it multiplies by every hour, by taking the 5th root of 52/40 or 13/10. this is approximately 0.167. we still need to add 1 to this, because we are multiplying by that number, not adding that amount of the number. now, we just calculate 4000 * (1.167)^19. use a calculator to get approximately 75232.6, or 75233.

the correct answers i think are b. and d.

give me brainliest if it is correct!