Equations
• x² + y = 0 ... (1)
• x² - 4x - y = 0 ... (2)
Answer -> (x, y) = (2, -4)
Step-by-step solution:
From equation 2,
-> y = x² - 4x ... (3)
• Substitute y into equation 1
-> x² + (x² - 4x) = 0
-> 2x² - 4x = 0
-> 2x² = 4x
-> x²/x = 4/2
-> x = 2
• Put x = 2 in equation 3
-> y = (2)² - 4(2)
-> y = 4 - 8
-> y = -4
The formula for simple interest is <em>I</em> = <em>prt</em>, where <em>I</em> is the amount of interest, <em>p</em> is the principal borrowed, <em>r</em> is the interest rate written as a decimal number, and <em>t</em> is the amount of time in years. First we find the amount of interest. He borrowed $35000 but paid back $46375. That means he paid 46375-35000 = $11375 in interest. We can now substitute our information into our interest formula:
11375=35000(<em>r</em>)(5)
11375=35000(5)(<em>r</em>) ----- remember that multiplication is commutative
11375=175000<em>r</em>
Divide both sides by 175000 to cancel it:
11375/175000 = 175000<em>r</em>/175000
0.065 = <em>r</em>
To convert this to a percentage, we multiply by 100:
0.065(100) = 6.5%
