Answer:
x ≈ - 5.32, x ≈ 1.32
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 )
Answer:
0.0021
Step-by-step explanation:
Answer:
answer is 7.5 miles
Step-by-step explanation:
30/8=3.75 mi in one hour
3.75*2=7.5 miles in 2 hours
hope it helps
Answer: the length of each of the two equal sides is 25 centimeters
Step-by-step explanation:
Let x represent the length of each of the two equal sides. This means that the total length of the two longer sides is 2x.
Let y represent the length of the third side.
The perimeter of a triangle is expressed as the sum of the length of each side of the triangle. The perimeter of the isosceles triangle is 65 centimeters. It means that
2x + y = 65 - - - - - - - - - 1
Each of the equal sides is 10 centimeters longer than the third side. This means that
x = y + 10
Substituting x = y + 10 into equation 1, it becomes
2(y + 10) + y = 65
2y + 20 + y = 65
2y + y = 65 - 20
3y = 45
y = 45/3 = 15
Substituting y = 15 into x = y + 10, it becomes
x = 15 + 10 = 25
