Answer:
x ≈ 1.32, x ≈ - 5.32
Step-by-step explanation:
Given
x² + 4x - 7 = 0 ( add 7 to both sides )
x² + 4x = 7
To complete the square
add ( half the coefficient of the x- term )² to both sides
x² + 2(2)x + 4 = 7 + 4
(x + 2)² = 11 ( take the square root of both sides )
x + 2 = ±
( subtract 2 from both sides )
x = - 2 ± 
Thus
x = - 2 -
≈ - 5.32 ( to 2 dec. places )
x = - 2 +
≈ 1.32 ( to 2 dec. places )
Change 1 hour 15 minutes = 1.25 hour because 15 ÷ 60 = 0.25 so we add 0.25 hour and change 2 3/4 to 2.75
Equation:
Multiply 2.75 × 1 = 2.75 ÷ 1.25 =
2.2 miles
I'm pretty sure this is correct
Answer:
sorry I dont know the way u put it makes no sense
Let x be the months and y be the cost.
Rate of increase of commodity A = 6/3 = $2 per month
Equation:
y = 2x + 4500
Rate of increase of commodity B = 2/4 = $0.5 per month
Equation:
y = 0.5x + 5400
Equating the costs,
2x + 4500 = 0.5x + 5400
1.5x = 900
x = 600 months
x = 600 / 12 = 50 years