the is just THIS ONE JIAN JUAN IS B
is the logical or/disjunction symbol.
means "
or
". Disjunction is commutative, which means
is equivalent to
.
So if
represents
and
represents
, then
means
or
.
Answer:
Option C is correct.
Step-by-step explanation:
A direct variation function is
y/x = k
i.e. we can say that the ratio of y and x is equal to a constant value k.
We will check for each Option given.
Option A
7/2 = 7/2
8/3 = 8/3
9/4 = 9/4
10/5 = 2
11/6 = 11/6
Option D is incorrect as y/x ≠ k as ratio of y/x for each value of table doesn't equal to constant
Option B
-3/2 = -3/2
-5/4 = -5/4
-6/6 = -1
-7/8 = -7/8
-8/10 = -4/5
Option B is incorrect as y/x ≠ k as ratio of y/x for each value of table doesn't equal to constant
Option C
10/-5 = -2
8/-4 = -2
6/-3 = -2
4/-2 = -2
2/-1 = -2
Option C is correct as y/x = k as ratio of y/x for each value in table c is equal to constant value -2
Option D
-3/-2 = 3/2
-3/1 = -3
-3/0 = 0
-3/1 = -3
-3/2 = -3/2
Option D is incorrect as y/x ≠ k as ratio of y/x for each value of table doesn't equal to constant .
SO, Option C is correct.
Let L be the low copper alloy and H be the high copper alloy.
We need 0.15L + 0.60H = 0.42 and L + H = 100
L=100 - H
Substituting this into the second equation for L, we get:
0.15(100-H) + 0.60H = 0.42(H+L)
15 - 0.15H + 0.60H = 0.42(H+100-H)
15 + 0.45H = 0.42(100)
0.45H = 42 - 15 = 27
H = 27/.45 = 60 lbs
Back substitution, L = 40 lbs.
