Answer:
x=# of boys
x+7=# of girls
x+x+7=25
2x+7=25
2x=25-7
2x=18
x=18/2
x=9 boys
x+7=16 girls
If you don't understand variables use trial and error.
Boys Girls
1 8
2 9
3 10
4 11
5 12
6 13
7 14
8 15
9 16 9+16=25 students
You could start this way...
Boys Girls
12 13
11 14
10 15
9 16 16 is 7 more than 9
solution:
we know that ,
u.v = ΙuΙ ΙvΙcosθ
here,
θ =60° (since the given triangle is equilateral triangle)
u.v = ΙuΙ ΙvΙcos60°
= 1 x 1 x 1/2
u.v = 1/2
now, u.w = ΙuΙ ΙwΙcosθ
= ΙuΙ x cos(60x2)
u.w = -1/2
The answer is 1.47
hope this help you
The triangles are not the same size so a dilation made the original one smaller and a translation moved it to map ABC to A'B'C'.