Answer:
w = 4 cm
Step-by-step explanation:
recall that the area of a triangle is given by
A = (1/2) x base length x height
we are given:
A = 10 cm²
base length = 5 cm
height = w
substituting the values above into the equation,
A = (1/2) x base length x height
10 = (1/2) x 5 x w
20 = 5w
w = 20/5
w = 4 cm
Answer:
Check pdf
Step-by-step explanation:
Money spent + money left over = total money
money spent + 9 = 30
We don't know the price of each shirt, so let x = price of 1 shirt.
Then, 3 shirts cost 3 times as much as x, or 3x.
She spent 3x.
3x + 9 = 30
Answer:
You can use either of the following to find "a":
- Pythagorean theorem
- Law of Cosines
Step-by-step explanation:
It looks like you have an isosceles trapezoid with one base 12.6 ft and a height of 15 ft.
I find it reasonably convenient to find the length of x using the sine of the 70° angle:
x = (15 ft)/sin(70°)
x ≈ 15.96 ft
That is not what you asked, but this value is sufficiently different from what is marked on your diagram, that I thought it might be helpful.
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Consider the diagram below. The relation between DE and AE can be written as ...
DE/AE = tan(70°)
AE = DE/tan(70°) = DE·tan(20°)
AE = 15·tan(20°) ≈ 5.459554
Then the length EC is ...
EC = AC - AE
EC = 6.3 - DE·tan(20°) ≈ 0.840446
Now, we can find DC using the Pythagorean theorem:
DC² = DE² + EC²
DC = √(15² +0.840446²) ≈ 15.023527
a ≈ 15.02 ft
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You can also make use of the Law of Cosines and the lengths x=AD and AC to find "a". (Do not round intermediate values from calculations.)
DC² = AD² + AC² - 2·AD·AC·cos(A)
a² = x² +6.3² -2·6.3x·cos(70°) ≈ 225.70635
a = √225.70635 ≈ 15.0235 . . . feet