slope = (y2-y1)/(x2-x1)
the first slope is 0 (horizontal line)
second slope is undefined (vertical line)
Given: lines l and m are parallel, and line t is a transversal.
angle pair result/justification
1 and 2 are equal (vertical angles)
6 and 8 are equal (corresponding angles)
1 and 4 are equal (alternate exterior angles)
4 and 8 are supplementary angles (i.e. add up to 180 degrees, a straight angle)
Note:
alternate angles are on opposite sides of the transversal, and each attached to a different (parallel) line.
If they are both enclosed by the parallel lines, they are alternate interior angles (examples: angles 2 and 3, 6 and 7)
If they are both outside of the two parallel lines, they are alternate exterior angles (examples: angles 1 and 4, 5 and 8)
Hello,
Let's assume f the age of the father,
s the age of the son.
<span>The age of a father is 2 less than 7 times the age of his son ==> f=7s-2 (1)
</span>
<span>In 3 years, the sum of their ages will be 52 ==>(f+3)+(s+3)=52 (2)
(2)==>f+s+6=52
==>f+s=46 (3)
(3) and (1) ==>7s-2+s=46
==>8s=48
==>s=6
f=46-6=40
</span>
