Question

Shawna, Dexter, and Tilana are solving the equation Negative 2.5 (5 minus n) + 2 = 15. Shawna says, "I can begin by dividing each side of the equation by –2.5 to get 5 minus n minus StartFraction 2 over 2.5 EndFraction = Negative StartFraction 15 over 2.5 EndFraction." Dexter says, "I can begin by distributing Negative 2.5 to get Negative 12.5 + 2.5 n + 2 = 15." Tilana says, "I can begin by multiplying each side of the equation by Negative StartFraction 1 over 2.5 EndFraction to get 5 minus n minus 0.8 = negative 6." Which students are correct? only Shawna and Tilana only Shawna and Dexter only Dexter and Tilana Shawna, Dexter, and Tilana

Answer 1

Answer:

All three students are correct

Step-by-step explanation:

Given

Equation: -2.5(5 - n) + 2 = 15

Required

Which students are correct

To determine which of the students are correct; we have to test each of their solutions

SHAWNA

Statement: Dividing each side of the equation by –2.5 to get 5 - n - 2/2.5 = -15/2.5

$\frac{-2.5(5 - n) + 2}{-2.5} = \frac{15}{-2.5}$

Split fractions

$\frac{-2.5(5 - n)}{-2.5} + \frac{2}{-2.5} = \frac{15}{-2.5}$

Simplify each fraction

$5-n - \frac{2}{2.5} = \frac{-15}{2.5}$

Shawna is correct...

DEXTER

Statement: Distributing -2.5 to get -12.5 + 2.5 n + 2 = 15.

$-2.5(5 - n) + 2 = 15$

Open brackets

$-12.5 + 2.5n + 2 = 15$

Dexter is also correct...

TILANA

$\frac{-1}{2.5}(-2.5(5 - n) + 2) = \frac{-1}{2.5} * 15$

Open brackets

$\frac{-1}{2.5}(-2.5(5 - n)) + \frac{-1}{2.5}(2) = \frac{-1}{2.5} * 15$

Simplify each bracket

$(5 - n) + \frac{-2}{2.5} = \frac{-15}{2.5}$

$(5 - n) - \frac{2}{2.5} = \frac{-15}{2.5}$

$5 - n - 0.8 = -6$

Tilana is also correct

Hence, all three students are correct

Answer 2

Answer:

All of them are correct

Step-by-step explanation: