Answer:
Step-by-step explanation:
Solution by substitution method
3x+5y=7
and 4x-y=5
Suppose,
3x+5y=7→(1)
and 4x-y=5→(2)
Taking equation (2), we have
4x-y=5
⇒y=4x-5→(3)
Putting y=4x-5 in equation (1), we get
3x+5y=7
⇒3x+5(4x-5)=7
⇒3x+20x-25=7
⇒23x-25=7
⇒23x=7+25
⇒23x=32
⇒x=32/23
→(4)
Now, Putting x=32/23
in equation (3), we get
y=4x-5
⇒y=4(32/23)-5
⇒y=(128-115)/23
⇒y=13/23
∴y=13/23 and x=32/23
Answer:
Step-by-step explanation:
30 + .40(30) = 30(1 + .40) = 30(1.4) = $42
Answer:
all values! x ∈ R
Step-by-step explanation:
The derivative f'(x) = 6x²-6x+12 is a parabola opening upward, with its (positive!) minimum at (0.5, 11.5). If the derivative is always positive, the function must be increasing everywhere!
Answer: the associative property of addition
Step-by-step explanation: when adding three or more terms, you can combine the middle terms with either the first term or the last term and as you add the results, the sum will be the same either way.