Answer:
see explanation
Step-by-step explanation:
In 13 - 17
Consider the factors of the constant term which sum to give the coefficient of the x- term
13
x² - x - 42 = (x - 7)(x + 6)
15
x² + x - 6 = (x + 3)(x - 2)
17
x² - 27x + 50 = (x - 25)(x - 2)
19
r² - 25 ← is a difference of squares and factors in general as
a² - b² = (a - b)(a + b) , thus
r² - 25
= r² - 5² = (r - 5)(r + 5)
You add the two numbers and divide them by two
Answer:
Step-by-step explanation:
They are all true
Answer:
a= 
or 
Step-by-step explanation:
Equate the equation to zero
-9a+2=0
-5a-4a+2=0
5a(2a-1)-2(2a-1)=0
Write out the factors
(5a-2)(2a-1)=0
Then equate each factor to zero
5a-2=0 OR 2a-1=0
5a=2 OR 2a=1
a= OR a=
a= or
