d) You have a <u>difference of squares</u>:
49y² - 9 = (7y)² - 3²
Recall the identity,
a² - b² = (a - b) (a + b)
So,
49y² - 9 = (7y - 3) (7y + 3)
e) Pull out the common factor 3 from each term:
3x² - 3x - 90 = 3 (x² - x - 30)
Now use the <u>sum-product method</u>. Notice that we can write 30 = 5 • 6, and 5 - 6 = 1, so
3x² - 3x - 90 = 3 (x + 5) (x - 6)
f) Same as in (e), use the <u>sum-product method</u>. Notice that 42 = 7 • 6, and -7 - 6 = -13, so
x² - 13x + 42 = (x - 7) (x - 6)
Perimeter=4h+4
If the base is 2 more than the height, it gives us the equation:
b=h+2
The equation for the perimeter of a rectangle can be though of as 2b+2h, so substituting in (h+2) for b from the first equation, we get 2(h+2)+2h.
This can be simplified to be 2h+4+2h or 4h+4
Answer:
(6,2)
Step-by-step explanation:
because math
Y= -2 - (the square root of) 21 and Y= -2+ (the square root of) 21