Answer:
Multiply 1st equation by 3
Step-by-step explanation:
To eliminate -3y, we must multiply the 1st equation by such a number that the -y becomes -3y. This can be done by multiplying the 1st equation by 3.
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Step-by-step explanation:

Answer:
Very little information is given, leaving room to multiple possible functions, however i would expect it to be y = 4x
Step-by-step explanation:
x * z = y
4 * z = 16
z = 16/4
z = 4
We are given ratio nickel to zinc to copper = 2:7:9.
From this ratio we can see that <em>ratio of nickel to zinc is 2:7</em>.
Let us assume number of pounds of nickel have to be used to create alloy that contains 4.9 lb of zinc is x pounds.
So, we can setup a proportion as :
x : 4.9 = 2:7
Or

On cross multiplication, we get
7x= 4.9× 2
7x = 9.8
Dividing both sides by 7, we get
x = 1.4.
<h3>Therefore, 1.4 pounds of nickel have to be used to create alloy that contains 4.9 lb of zinc.</h3><h3 />
The area of a triangle can be calculated as half the product of base length and height. We want the area to be no greater than 10 in².
a) (1/2)(4)(2x-3) ≤ 10
b) 4x -6 ≤ 10 . . . . . simplify
... 4x ≤ 16 . . . . . . . .add 6
... x ≤ 4 . . . . . . . . . divide by the coefficient of x
c) The maximum value of (2x -3) in is (2·4 -3) in = 5 in.
The triangle should be no more than 5 in high to have an area less than 10 in².