Answer:
Step-by-step explanation:
- x + y + z = -3 --> (1)
- 3y - z = 4 --> (2)
- 2x - y - 2z = -5 --> (3)
<u>Add up (1) and (2)</u>
- x + 3y + y + z - z = -3 + 4 ⇒ x + 4y = 1 --> (4)
<u>Double (2) and subtract from (3)</u>
- 2x - y - 2z - 2(3y - z) = -5 - 2(4) ⇒ 2x - y - 2z - 6y + 2z = -5 - 8
- 2x - 7y = -13 --> (5)
<u>Double (4) and subtract (5)</u>
- 2(x + 4y) - 2x + 7y = 2 + 13 ⇒ 2x + 8y - 2x + 7y = 15 ⇒ 15y = 15 ⇒ y = 1
<u>Finding x</u>
- x + 4(1) = 1 ⇒ x = 1 - 4 ⇒ x = -3
<u>Finding z</u>
<u>So the answer is: </u>
Answer:
see explanation
Step-by-step explanation:
given that r varies jointly with x and y then the equation relating them is
r = kxy ← k is the constant of variation
To find k use the condition r = 15 when x = 3 and y = 4
k = = = 1.25
r = 1.25xy ← equation of variation
When x = 16 and y = 1.25, then
r = 1.25 × 16 × 1.25 = 25
Answer:
A.
As x decreases in value, f(x) decreases in value.
As x increases in value, f(x) increases in value.
Step-by-step explanation:
As we move our eyes towards the right following the curve, we see that the y-values are larger and larger. As we move to the right following the curve, the values of the x-variable in the horizontal axis are increasing. Then as x increases, the values of f(x) also increase.
On the other hand, if we move our eyes to the left following the curve, this way looking into what values the function adopts for smaller and smaller values of x, we see that the f(x) values decrease (the curve goes down).
Then, to summarize:
a) As we move to the right, thus increasing the values of x, we see the values of f(x) increase
b) As we move to the left, thus decreasing the values of x, we see the values of f(x) decrease.
Answer:
20 × 9= 180
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