Answer:
y= 2.5
x= 3
Step-by-step explanation:
multiply eqn 2 by 5
5x +20y =65
eqn 2 -1
20-2)y=65-20
18y=45
y=2.5
x+4×2.5 =13
x+10=13
x=3
Answer:
p = 25,20 cm
h = 34,32 cm
A(min) = 864,86 cm²
Step-by-step explanation:
Let call p and h dimensions of a poster, ( length , and height respectively) and x and y dimensions of the printed area of the poster then
p = x + 8 and h = y + 12
Printed area = A(p) = 384 cm² and A(p) = x*y ⇒ y = A(p)/x
y = 384 / x
Poster area = A(t) = ( x + 8 ) * ( y + 12 ) ⇒ A(t) = ( x + 8 ) * [( 384/x ) + 12 ]
A(t) = 384 + 12x + 3072/x + 96 A(t) = 480 + 3072/x + 12x
A(t) = [480x + 12x² + 3072 ] / x
A´(t) = [(480 + 24x )* x - (480x + 12x² + 3072]/x²
A´(t) = 0 [(480 + 24x )* x - 480x - 12x² - 3072] =0
480x + 24x² -480x -12x² - 3072 = 0
12x² = 3072 x² = 296
x = 17,20 cm and y = 384/17,20 y = 22,32 cm
Notice if you substitu the value of x = 17,20 in A(t) ; A(t) >0 so we have a minimun at that point
Then dimensions of the poster
p = 17,20 + 8 = 25,20 cm
h = 22.32 + 12 =34,32 cm
A(min) = 25,20 *34.32
A(min) = 864,86 cm²
Answer:
Sorry though i dont know how to speak Spanish
1 yard = 3 feet.
Multiply the length of the truck by 3 to get total feet:
6 x 3 = 18 feet.
Subtract the length of the truck from the length of the parking space:
20 - 18 = 2 feet
1 foot = 12 inches.
Multiply 2 feet by 12:
2 x 12 = 24 inches longer.
3.88888=3.88888/1=38.8888888
so lets ssay our repeating decimal = a fraction x
x=3.888 is true
multiply by 10
10x=38.8888
now subtract fir frist eqation from second
10x-x=38.8888-3.888888
9x=35
divide both sides by 9
x=35/9
x=3 and 7/9
anser is 3.88=3 and 7/9