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)
Solve like an equation,
You need x by itself.
Since x is on the denominator, multiply both sides by x to clear the fraction.
Tan 12 = 10/x
x Tan12 = 10
Divide both sides by Tan12
x = 10/(Tan12)
x = 47
The answer is (0,-3) and (0-1)
hope this helped
I would use is over of equals percent over 100 is woudl be 120% and of would be 75 then you would put x over 75