Algebra public opinion polls reported in newspapers are usually given with a margin of error. for example, a poll with a margin of error of ±5% is considered accurate to within plus or minus 5% of the actual value. a poll with a stated margin of error of 6.3% predicts that candidate towne will receive 51% of an upcoming vote. write and solve an equation describing the minimum and maximum percent of the vote that candidate towne is expected to receive.

Minimum percent of the vote that candidate Towne is expected to recieve:

m=51% - 6.3% * 51% =47.787%

Maximum percent of the vote that candidate Towne is expected to recieve:

M=51% + 6.3% * 51% = 54.213%

Solution:

Margin of error: E=6.3%

Minimum percent of the vote that candidate Towne is expected to recieve:

m=51% - E * 51%

m=51% - 6.3% * 51%

m=51% - 51% * 6.3 / 100

m=51% - 3.213%

m=47.787%

Maximum percent of the vote that candidate Towne is expected to recieve:

M=51% + E * 51%

M=51% + 6.3% * 51%

M=51% + 51% * 6.3 / 100

M=51% + 3.213%

M=54.213%

x = ±sqrt(10)

step-by-step explanation:

5 - 2x² = -15

subtract 5 from each side

5-5 - 2x² = -15-5

-2x^2   = -20

divide by -2 on each side

-2x^2   /-2= -20/-2

x^2 =10

take the square root on each side

sqrt(x^2 )=±sqrt(10)

x = ±sqrt(10)

check:

5 - 2x² = -15

+sqrt(10)

5 - 2(sqrt(10))² = -15

5 -2(10) = -15

5 -20 = -15

-15 = -15

-sqrt(10)

5 - 2(-sqrt(10))² = -15

5 -2(10) = -15

5 -20 = -15

-15 = -15