The first thing you should do is make the equation 4x+1=13 to find x. You then remove 1 from each side to get 4x=12, and then you divide by 4 to get x=3.
The next thing you do is make the equation -2y+8(3)=y+2(3)
Which simplified is -2y+24=y+6. You then add 2y to each side and remove 6 from each side to get the 18=3y. You then divide by 3 to get y=6.
He planted 92 of those because 12 times 6 is 72 and 72 plus 20 is 92 therefore the answer is 92
ANSWER for the first one:
A=a+b/2*h
A= 4.5+9/2*6
A= 40.5 cm2
ANSWER for the second one:
9*3= 27
3*3= 9
9*3= 27
A= 63 cm2
If you make a proportion,
12 18
--- = ---
10 x
when you cross multiply
12x=180
x=15
EF= 15