Answer:
B. 10
Step-by-step explanation:
First, we need to recognize that the two triangles are similar (the triangle with a leg value of 21 and the triangle with a leg value of 4 and hypotenuse x)
Let's first label the leg of the second triangle as y.
Then, we can set up this equation

Cross multiplying gives us
84=y^2
So, y=sqrt(84) or 2 sqrt(21).
Now, using the pythagorean theorem, we get
4^2+2sqrt(21)^2=x^2
100=x^2
x=10
The last choice, f(x)=1/4(4ˣ⁻⁻¹)-4, is correct.
Substituting our values for x, we have:
f(2) = 1/4(4²⁻¹)-4 = 1/4(4¹) - 4 = 1/4(4) - 4= 1 - 4 = -3
f(3) = 1/4(4³⁻¹)-4 = 1/4(4²) - 4 = 1/4(16) - 4 = 4 - 4 = 0
f(4) = 1/4(4⁴⁻¹)-4 = 1/4(4³) - 4 = 1/4(64) - 4 = 16 - 4 = 12
All of the data points fit.
The percent decrease is found by using the formula (original price - new price)/(original price). The percent decrease is then (2.49 - 1.99)/2.49 = 0.20 = 20%. A percent increase is found by using the formula (new price - original price)/(original price). The percent increase is then (2.49 - 1.99)/1.99 = 0.25 = 25%. The percents of change are not the same. The percent increase is greater.
WX/RS = (28 ft)/(40 ft) = 7/10
Selection D is appropriate.
Answer:
y
=
−
4
x
+
3
Step-by-step explanation: