4x2 + 28x + 49 = 0
(x+) =
Answer: x = - 3.5
Step-by-step explanation:
Rewrite the equation by completing the square.
4x2 + 28x + 49 = 0
Completing the square method :
Divide through by the Coefficient of x^2
x^2 + 7x + (49/4) = 0
a = 1, b = 7, c = 49/4
Move c to the right side of the equation
x^2 + 7x = - 49/4
Complete the square on the left hand side by squaring its half of the x term
(7/2)^2 = (49/4)
Add the output to both sides of the equation
x^2 + 7x + (49/4) = - (49/4) + (49/4)
(x + 7/2)^2 = 0
Square root of both sides
x + 7/2 = 0
x = - 7/2
x = - 3.5
Answer:
x = - 3.5
Step-by-step explanation:
The height of the triangle is 2 kilometer.
A triangle is a 3-sided polygon. The sum of the angles in a triangle add up to 180 degrees. The sides of a triangle are the length, base and the hypotenuse.
The area of a triangle = × base × height
Let:
t represent the height of the triangle.
Base = 2 x t = 2t
Area = 4
4 = × 2t x t
Multiply both sides of the equation by 2
8 = 2t²
Divide both sides by 2
4 = t²
Find the square root of both sides of the equation
t = 2 kilometer.
To learn more, please check: brainly.com/question/24865193?referrer=searchResults
Let the distance be x miles
Time = Distance / speed
Time taken by Mike to go to his friend's house = x / 40 hours
Time taken by him to return = x / 45 hours
Total time = x / 40 + x / 45 = 4 hours
= 9x + 8x = 1440 miles
17x = 1440
= x = 1440 ÷ 7
= x = 84.706
Time taken to return home = 84.706 /45= 1.882 hours .
Therefore , Mike took1.882hoursto reach home .
How to solve equation x/3-4=10?