***(2x²+6x-8):(x+5)=2x-4
-2x²-10x
⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻
-4x-8
4x+20
⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻
12 ⇒ A. statement is true.
***When x=-5⇒2*(-5)²+6*(-5)-8=12⇒B. statement is true.
***2x²+6x-8 can also be written as (x+5)*(2x-4)+12 so (x+5) is a factor of 2x²+6x-8⇒C. statement is true.
***When x=5⇒2*5²+6*5-8=72 is not 12⇒D. statement is not true
***(2x²+6x-8):(x+5)=2x+16
-2x²+10x
⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻
16x-8
-16x+80
⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻
72⇒F. statement is not true
***E. statement is not true.
Answer:
This image show how to divide a given line segment into a number of equal parts by using a compass and ruler. First, draw the line AB. Secondly, draw a line above and divide into 5 equal distances to make a line AC. Third, using a compass by getting the distance of point C and B to be equal in the distance of point A and D, also getting the distance of point C to A to be equal to point B and D, then to make the Line DB. Finally divide into 5 equal parts by compass.
Step-by-step explanation:
1. Given any triangle ABC with sides BC=a, AC=b and AB=c, the following are true :
i) the larger the angle, the larger the side in front of it, and the other way around as well. (Sine Law) Let a=20 in, then the largest angle is angle A.
ii) Given the measures of the sides of a triangle. Then the cosines of any of the angles can be found by the following formula:
a^{2}=b ^{2}+c ^{2}-2bc(cosA)
2.
20^{2}=9 ^{2}+13 ^{2}-2*9*13(cosA) 400=81+169-234(cosA) 150=-234(cosA) cosA=150/-234= -0.641
3. m(A) = Arccos(-0.641)≈130°,
4. Remark: We calculate Arccos with a scientific calculator or computer software unless it is one of the well known values, ex Arccos(0.5)=60°, Arccos(-0.5)=120° etc
It is a single-winner voting system criterion used to compare such systems.