F(3) means x =3 and x = 3 > -1 (f(x) = x^2 if x > -1)
so
f(3) = x^2 = 3^2 = 9
Answer
C . 9
13.15 ounces of 72% acid and 71.85 ounces of 25% acid are needed
<u>Step-by-step explanation:</u>
Total mass of acid required= 85 ounces
Let the mass of 72% acid be 'a'
Let the mass of 25% acid be 'b'
a + b = 85
b = 85-a
85(40/100) = a(72/100) + b(25/100)
85(2/5) = a(72/100) +(85- a) (25/100)
34 = (72a/100) + (2125/100) - (25a/100)
34 - (2125/100) = (72a + 25a) /100
(3400-2125)/100 = 97a /100
97a = 1275
a = 13.15 ounces
b = 85 - 13.14
b = 71.85 ounces
13.15 ounces of 72% acid and 71.85 ounces of 25% acid are needed
They have many answers so find the least one
Answer:
<em>h = 8.54 units</em>
Step-by-step explanation:
<u>The Law of Cosines
</u>
It relates the length of the sides of a triangle with one of its internal angles.
Let a,b, and c be the length of the sides of a given triangle, and x the included angle between sides a and b, then the following relation applies:
Since we know the values of all three side lengths, we solve the equation for x:
For the triangle ABC in the image, a=10, b=15, c=13, thus:
Thus, A = 58.67°
For the right triangle of height h and hypotenuse 10, we use the sine ratio:
Solving for h:
h = 8.54 units