Let the width of the rectangle be x
Then length =x-4
Area=x(x-4)=140
x²-4x=140
x²-4x-140=0
x²-14x+10x-140=0
x(x-14)+10(x-14)=0
(x-14)(x+10)=0
Therefore,length=14 cm and width=10 cm
Answer:
Step-by-step explanation:
Given that,
The height of the tree, h = 14 ft
The height of the shadow, b = 16 ft
We need to find the angle of elevation of the sun from the ground. Let the angle be θ. We can use trigonometry to find it. So,
So, the required angle of elevation of the sun is equal to 
.
Think of two ropes next to each other. Draw a picture if it helps. To find how much longer, start with the longer one and subtract the shorter length to get the difference, or “how much longer.”
To subtract fractions they have to be changed to the same denominator. First change 3 2/3 to a complex fraction; multiply the coefficient 3 times the denominator 3, then add the numerator. 3X3=9. 9+2=11 . 11 is now numerator, use same denominator. So you get 11/3. Then change denominator to 9. To do this you have to multiply by what? You would multiply by 3. Do the same to the numerator: 11 X 3=33. The fraction becomes 33/9. Now you can subtract. Now that both have the same denominator, you just subtract the numerators. 33-8=25. So, 33/9-8/9= 25/9
Answer:
x = -1
Step-by-step explanation:
7(4x+1)−3x=5x−13
Distribute
28x +7 -3x = 5x -13
Combine like terms
25x+7 = 5x-13
Subtract 5x from each side
25x-5x +7 = -13
20x +7 = -13
Subtract 7 from each side
20x+7-7 = -13-7
20x = -20
Divide by 20
20x/20 = -20/20
x = -1
