What two methods are the best choices to factor this expression? 18x2-8

-Factor by grouping.

-Factor out the GCF.

-Use the difference of squares rule.

-Use the perfect square trinomial rule.

Step-by-step explanation:

Given the expression 18x²-8, the best method to factor this expression are Factor by grouping and by factoring out the greatest common factor.

Step 1: Factor by grouping

Factor by grouping is done by creating a smaller groups from each term in the expression as shown;

18x² = (2*3*3* x²)

8 =  2*2*2

18x²-8 = (2*3*3* x²) - (2*2*2)

Step 2: Then we will factor out the greatest common factor (GCF) in the expression. GCF is the value that is common to both terms of the expression. The only common term in this case is 2.

let soccer = x and golf = y

part a

1st equation: x + y = 125

2nd equation: x = y +45

part b

replace x in the 1st equation with the 2nd one:

y + 45 + y = 125

simplify:

2y + 45 = 125

subtract 45 from each side:

2y = 80

divide both sides by 2:

y = 80/2

y = 40

she plays golf for 40 minutes.

part c

no because she plays soccer for 45 minutes longer than golf 40 +45 =   85 minutes, not 80 minutes.

yes

step-by-step explanation:

yes