Answer:
a = -3/2
Step-by-step explanation:
3(6a+12)=9
Divide each side by 3
3/3(6a+12)=9/3
6a+12 = 3
Subtract 12 from each side
6a+12-12 = 3-12
6a = -9
Divide by 6
6a/6 = -9/6
a = -3/2
F
Triangle equals 180
42+42=84
What is 180-84
That would be the next angle
Answer:
9( 1 + 4w)
Step-by-step explanation:
So if you're simplifying then you need to find the greatest common factor. The GCF is 9.
Perpendicular lines have negative reciprocal slopes. So if the slope is -2/5...to find the negative reciprocal, " flip " the slope and change the sign.
So we flip -2/5 and we get 5/-2...and now we change the sign...and we get 5/2. So our perpendicular slope will be 5/2.
Answer:
15°.
Step-by-step explanation:
1. Angles ADC and CDB are supplementary, thus
m∠ADC+m∠CDB=180°.
Since m∠ADC=115°, you have that m∠CDB=180°-115°=65°.
2. Triangle BCD is isosceles triangle, because it has two congruent sides CB and CD. The base of this triangle is segment BD. Angles that are adjacent to the base of isosceles triangle are congruent, then
m∠CDB=m∠CBD=65°.
The sum of the measures of interior angles of triangle is 180°, therefore,
m∠CDB+m∠CBD+m∠BCD=180° and
m∠BCD=180°-65°-65°=50°.
3. Triangle ABC is isosceles, with base BC. Then
m∠ABC=m∠ACB.
From the previous you have that m∠ABC=65° (angle ABC is exactly angle CBD). So
m∠ACB=65°.
4. Angles BCD and DCA together form angle ACB. This gives you
m∠ACB=m∠ACD+m∠BCD,
m∠ACD=65°-50°=15°.
Have a good Day!