Answer:
18
Step-by-step explanation:
Remark
This is one of those questions that can throw you. The problem is that do you include the original rectangle or not. The way it is written it sounds like you shouldn't
However if you don't the question gives you 2 complex answers. (answers with the sqrt( - 1) in them.
Solution
Let the width = x
Let the length = x + 5
Area of the rectangle: L * w = x * (x + 5)
Area of the smaller squares (there are 2)
Area = 2*s^2
x = s
Area = 2 * x^2
Area of the larger squares = 2 * (x+5)^2
Total Area
x*(x + 5) + 2x^2 + 2(x + 5)^2 = 120 Expand
x^2 + 5x + 2x^2 + 2(x^2 + 10x + 25) = 120 Remove the brackets
x^2 + 5x + 2x^2 + 2x^2 + 20x + 50 = 120 collect the like terms on the left
5x^2 + 25x + 50 = 120 Subtract 120 from both sides.
5x^2 + 25x - 70 = 0 Divide through by 5
x^2 + 5x - 14 = 0 Factor
(x + 7)(x - 2) = 0 x + 7 has no meaning
x - 2 = 0
x = 2
Perimeter
P = 2*w + 2*L
w = 2
L = 2 + 5
L = 7
P = 2*2 + 2 * 7
P = 4 + 14
P = 18
Answer: the old price for 1 liter is $0.3
Step-by-step explanation:
Let x represent the old price for 1 liter of petrol.
Last week a man bought 20 liters at the old price. This means that the total amount that the man paid for 20 liters is 20x.
The cost of petrol rises by 2 cents a liter. This means that the new price per liter is x + 2/100 = x + 0.02
This week he bought 10 liters at the new price. This means that the total amount that the man paid for 10 liters is
10(x + 0.02)
= 10x + 0.2
Altogether, the petrol costs $9.20. This means that
20x + 10x + 0.2 = 9.2
30x + 0.2 = 9.2
30x = 9.2 - 0.2
30x = 9
x = 9/30
x = 0.3
Answer:
Step-by-step explanation:
2x² - 7x - 3 = 1
Step 1: 2x² - 7x - 4 = 0
Step 2: incorrect.
Use Quadratic Formula to solve for roots.
x = [7 ± √(7² – 4·2(-4))] / [2·2]
= [7 ± √81] / 4
= [7 ± 9] /4
= -0.5, 4
Answer:
#5 the sum would be on the right side because it is positive
The answer is 29 degrees because a right angle is 90 degrees and if you subtract 90-61= 29.
