Answer:
when you divide both sides of any inequality by a negative number, you need to greater than the inequality symbol
Step-by-step explanation:
have a great day ahead :)
Hope this will help u..............
Answer:
20kg of 25% copper alloy
30kg of 60% copper alloy
Step-by-step explanation:
There are 2 kinds of metal, first metal(A) have 25% copper while the second metal(B) has 60% copper. The metalworker want to create 50kg of metal, which means the total weight of both metals is 50kg (A+B = 50). The metalworker also want the metal made of a 46% which is 23kg(0.25A + 0.6B = 0.46*50). From these sentences, we can derive 2 equations. We can solve this with substitution.
A+B = 50
A= 50-B
Let's put the first equation into the second.
0.25A + 0.6B = 0.46 *50
0.25(50-B) + 0.6B =23
12.5 - 0.25B + 0.6B =23
0.35B=23 -12.5
B= 10.5/ 0.35= 30
Then we can solve A
A= 50-B
A= 50-30
A=20
The lines that are the directrices of the ellipse is B. x = −3.25 and x = 9.25.
<h3>How to calculate the ellipse? </h3>
From the information given, the equation of parabola will be:
= (x - 3)²/5² + (y - 2)²/3² = 1
Hence, h = 3, k = 2, a = 5, b = 3
e = ✓1 - ✓3²/5²
E = 4/5 = 0.8
The directix will be:
x = 3 + 5/0.8
x = 9.25
x = 3 - 5/0.8
x = -3.25
Therefore, lines that are the directrices of the ellipse is x = −3.25 and x = 9.25.
Learn more about ellipse on:
brainly.com/question/16904744
12/60 students chose science fiction
Approximately x/150 students prefer sf
60x = 1800
x = 30
30/150 students are assumed to prefer sf
30/150 = x/100
150x = 3000
x = 20
20/100 students are likely to prefer sf
Mr. Rodriguez made a reasonable estimate for the approximate percentage of students that prefer science fiction, because if 12/60 is equivalent to 30/150 which refers to the number of students who can be assumed to prefer science Fiction out of the whole school. Considering we need to identify what 30/150 as a percentage is, we can reduce it down to 1/5 to make I easier, then divide 1 by 5 to get .2
.2 as a percentage is 20%, so his inference was indeed reasonable.
(♥ω♥*)Brainliest Please(♥ω♥*)
