Answer:
x=1; y=2; z=3
Step-by-step explanation:
Rearrange for convince:
2y-4z+6x = -2
-4y+2z-3x=-5
-6y+3z+4x=1
Now we take to pairs and eliminate the same var.:
2y-4z+6x = -2 *2
-4y+2z-3x=-5
and
-4y+2z-3x=-5 *-3
-6y+3z+4x=1. *2
We get:
4y-8z+12y=-4
-4y+2z-3x=-5
= -6z+9x=-9
and
12y-6x+9x=15
-12y+6x+8x=2
= 17x=17
We now know x = 1, so z is:
-6z+9=-9
-6z=-18
z=3
Let’s grab the first formula and find y:
6+2y-12=-2
6+2y=10
2y=4
y = 2
Answer:
1. 424
2.471
3.512
Step-by-step explanation:
1. 10×12+8×10+8×13+8×15
=120+80+104+120
=424
2. 5×24+9×24+9×15+9×15
=120+216+135
=471
3. 24×16+2×24+2×20+2×20
=384+48+40+40
=512
Answer:
Tell her to do more practices in math. You can also recommend her here at Brainly if she finds hard questions to solve.
Step-by-step explanation:
20/28 are female. Since there are 8 male students you just have to subtract 28-8 and you'll get the female total.
Answer:
15.5 ft²
Step-by-step explanation:
The area (A) of a regular polygon is calculated as
A = 
pa ( p is the perimeter and a the apothem )
Here side of regular pentagon is 3 ft, thus
perimeter = 5 × 3 = 15, so
A = 0.5 × 15 × 2.06 ≈ 15.5 ft ( to the nearest tenth )
