The solution set is basically when are they equal. to figure this out we must set them equal. So so we will move some stuff around
x+y=5
y=5-x
y=x^2-25
we know that when they are equal their x and y values are equal. So so we know that their y values are the same so we can say:
y=y
this does not direarly help but looking above we know what both of the y's equal. so:
5-x = x^2-25
we want to set this equal to zero
0 = x^2 +x - 30
now we factor
0 = (x + 6) * (x - 5)
the only way to multiply 2 things together and get zero is for one of those things to equal 0. So so we know that to be zero one of the answers in parenthesis has to equal 0. so:
0 = (x + 6 =0) * (x - 5=0)
So now we solve for both parenthesis
x+6=0
x=-6
x-5=0
x=5
x=-6,5
I’m not 100% about this answer but i’m pretty sure it’s going to be 40/120. i hope this helped a little
Complete question :
In Hawaii a volcano is about to explodel At 6:00 am a device placed inside the volcano
measures the temperature at 69.5 degrees Celsius. Every 3 minutes the temperature
rises 1/5 a degree. If the Volcano explodes at 145.5 degrees Celsius how many hours do
they have to evacuate a nearby city?
Will Mark BRAINLIEST to the correct answer
Answer:
19 hours
Step-by-step explanation:
Given that:
Temperature of volcano at 6:00 am = 69.5°C
Average rise in temperature per 3 minute = 1/5
Hence, rise in temperature per minute = 0.0666666°C
Temperature at which volcano will explode = 145.5°C
Hence, change in temperature :
(145.5°C - 69.5°C) = 76°C
Hence, temperature will have to rise by 76°C
Rise in temperature / rate of temperature increase
= 76°C / 0.0666666°C
= 1140.0011 minutes
= 1140.0011 / 60
= 19.0000019 hours
= 19 hours
