You have to add 20 to 70 to make 90
Well a straight line is 180 degrees right? So the angle next to the outside 125 is 180- 125. The angles of a triangle also add up to 180. So if you know two angles of a triangle you can find the third one.
Note that subtracting a negative number from another number is equivalent to adding the magnitude of the negative number to the other number. Thus,
subtracting -1 2/3 from 5 1/2 is equivalent to adding 1 2/3 to 5 1/2.
Here the LCD is 3(2) = 6. Let's add 1 4/6 to 5 3/6. We get 6 7/6, or more properly, 7 1/6 (answer).
These are steps to construct a square.
Step 1:
Use a straightedge to draw line m and label a point on the line as point F.
Draw a line m and label a point F on it.
Step 2:
Construct a line perpendicular to line m through point F. Label a point on this line as point G.
Draw the line FG perpendicular to the line m.
Step 3:
With the compass open to the desired side length of the square, place the compass point on point F and draw an arc on line m and an arc on FG. Label the points of intersection as H and K.
Draw the sides FH and FK of the square.
Step 4:
Without changing the compass width, place the compass point on H and draw an arc in the interior of ∠HFK.
This is the first step to draw the fourth vertex of the square.
Step 5:
Keeping the same compass width, place the compass on point K and draw an arc in the interior of ∠HFK to intersect the previously drawn arc. Label the point of intersection as point J.
Draw the fourth vertex of the square and label it as J.
Step 6:
Use the straightedge to draw JH and JK.
Join JH and JK to complete the square.
To do this you have to cross multiply so you would do:
25/(f+2)=5/3
25*3=5(f+2)
75=5f+10
65=5f
13=f