Answer:
ttd2
Step-by-step explanation:
Minus 12x both sides
0=5x^2-12x+9
use quadratic formula
for 0=ax^2+bx+c
x=
given
5x^2-12x+9
a=5
b=-12
c=9
remember: i=√-1
<u>Let's take this problem step-by-step</u>:
<u>The ;unlabeled angle' adjacent to the 'outside angle of measure 78°'</u>
⇒ is on a straight line
⇒ sum of angle measure = 180 degrees

<u>Now we know:</u>
⇒ sum of all angles in a triangle ⇒ 180°
<u>Let's put that in equation form and solve:</u>

<u>Answer: 21°</u>
<u></u>
Hope that helps!
#LearnwithBrainly
Answer:
A = 3
Step-by-step explanation:
Given
(5x² + 3x + 4) - (2x² + 5x - 1)
Remove the parenthesis from the first and distribute the second by - 1
= 5x² + 3x + 4 - 2x² - 5x + 1 ← collect like terms
= 3x² - 2x + 5
In the form Ax² + Bx + C
with A = 3