T = total cost for music school
L = # of lessons
T = $1,190 + ($40 × L)
T = $1,190 + ($40 × 12)
T. = $1,190 + $480
T = $ 1,670 for 12 lessons
X = 7. 7 x 4 = 28 and 28 + 3 = 31.
31>27
Answer:
X=51/7, Y= -36/7
Step-by-step explanation:
X/3 + 2y/3 = -1 equ 1
X - y/3 = 9 equ 2
eliminate X/3.
X/3 + 2y/3 = -1..... x 1 ( co-efficient of X in equ2 )
X - y/3 = 9 ...... x 1/3 ( co-efficient of X in equ1 )
X/3 + 2y/3 = - 1 equ 3
-
X/3 - y/9 = 3 equ 4
0 + 7y/9 = -4
y = -36/7
( input the value of y into equ 4 )
X/3 -y/9 = 3
X/3 - (-36/7)/9 = 3
X/3 + 36/63 = 3
X/3 = 3 - 36/63
X/3 = 153/63
63X = 459
X = 459/63
X = 51/7.
Now, check the picture below
the area of the cross-sections, is really the same area as the rectangular faces, so, just use those areas, since they're the same
32/850 are defective
22000/850=25.88
25.88×32=828.23
round down to 828
out of 22,000 widgets 828 can be expected to he defective
