The value of x is 
Explanation:
The expression is 
Adding 
to both sides of the equation, we get,
Using log definition, if 
then 
, we have,
Using exponent rule, 
,
Simplifying, we have,
Dividing both sides by 9, we have,
Simplifying,
Thus, the value of x is
<u>Solution:</u>
Let us rewrite 30% as
. Let x be the missing number.
and we are done.
<u>Note:</u> You can do the same method by saying that 30% = 0.3 which would then show us that 60 divided by 0.3 is 200.
Answer:
−0.8x+4.8y+16
Step-by-step explanation:
4(0.5x+2.5y−0.7x−1.3y+4)
=(4)(0.5x+2.5y+−0.7x+−1.3y+4)
=(4)(0.5x)+(4)(2.5y)+(4)(−0.7x)+(4)(−1.3y)+(4)(4)
=2x+10y−2.8x−5.2y+16
=−0.8x+4.8y+16
What is the question to your problem?
Answer:
Dimensions of the poster
Width 29.10 cm
Height 38.80 cm
A(min) = 1129.08 cm²
Step-by-step explanation:
Printed area = 390 cm² = Ap
Lets call x and y dimensions of printed area
x width
y height
Then Ap = x*y and
y = Ap/x ⇒ y = 390/x
Then total area of the poster is:
A(t) = ( x + 12 ) * ( y + 16 ) and y = 390/x
A as a function of x
A(x) = ( x + 12 ) * ( 390/x + 16 ) ⇒ A(x) = 390 + 16x + 4680/x + 192
A(x) = 582 + 16x + 4680/x (1)
Taking derivatives
A´(x) = 16 - (4680/x²) ⇒ A´(x) = 0
[ 16x² -4680] /x² = 0 16x²- 4680 = 0 ⇒ x² = 4680/16
x = 17.10 cm and y = 390/x y = 390/17.10 y = 22.80 cm
A(t) = ( 17.10 + 12 ) * ( 22.80 + 16 )
A(t) = 29.10 * 38.80
A(t) = 1129.08 cm²
If we substitute in equation (1) the value of x ( 17.10) we see A(x) > 0
Then there is a minimun at the point x = 17.10
