Answer:
See below.
Step-by-step explanation:
a.
The first figure has 1 square. The second figure has a column of 2 squares added to the left. The third figure has a column of 3 squares added to the left. Each new figure has a column of squares added to the left containing the same number of squares as the number of the figure.
b.
Figure 10 has 1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 + 10 = 55 squares.
c.
The formula for adding n positive integers starting at 1 is:
1 + 2 + 3 + ... + n = n(n + 1)/2
For figure 55, n = 55.
n(n + 1)/2 = 55(56)/2 = 1540
d.
Let's use the formula set equal to 190 and solve for n. If n is an integer, then we can.
n(n + 1)/2 = 190
n(n + 1) = 380
We know that 380 = 19 * 20, so n = 19.
Answer: yes
e.
Use the formula above,
S = n(n + 1)/2, where S is the sum.
f.
n(n + 1) = 1478
38 * 39 = 1482
37 * 38 = 1406
Answer:
points (8, 0) and (3, 0)
Step-by-step explanation:
Here we're being asked to find the roots of this quadratic equation.
Set f(x) = 3(x² - 11x + 24 = 0.
This factors into f(x) = 3(x - 8)(x - 3) = 0.
Then x - 8 = 0 and x - 3 = 0, yielding x = 8 and x = 3. These correspond to the points (8, 0) and (3, 0).
(x^2-1)(x^2+7) should be your answer
