+1859 I'm thinking of a number. My number has the property that its square is equal to $270$ more than five times the number. Enter all numbers that have this property.
+947
I'm thinking of a number. My number has the property that its square is equal to $270$ more than five times the number. Enter all numbers that have this property.
x2 = 5x + 270
Get everything on the left x2 – 5x – 270 = 0
I couldn't figure out how to factor this, so I used Desmos to plot y = x2 – 5x – 270
which confirmed that the roots are not integers. Where the parabola crosses the
x-axis shows the roots are a little smaller than –14.1 and a little larger than +19.1.
You will have to use the quadratic formula if you want exact numbers, if you can
use exact to describe a number that includes plus/minus the square root of 1105.
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