Solve by completing the square.r2+16r=43Write your answers as integers, proper or improper fractions in simplest form, or decimals rounded to the nearest hundredth.r=_____ or r=_____
Q. Solve by completing the square.r2+16r=43Write your answers as integers, proper or improper fractions in simplest form, or decimals rounded to the nearest hundredth.r=_____ or r=_____
Rewrite equation: Rewrite the equation in the form of r2+br=c. The given equation is already in this form: r2+16r=43.
Complete the square: Add the square of half the coefficient of r to both sides to complete the square.The coefficient of r is 16, so half of it is 8, and the square of 8 is 64.Add 64 to both sides of the equation:r2+16r+64=43+64r2+16r+64=107
Factor left side: Factor the left side of the equation.The left side is a perfect square trinomial:(r+8)2=107
Take square root: Take the square root of both sides of the equation.(r+8)2=±107r+8=±107
Isolate variable: Solve for r by isolating the variable.Subtract 8 from both sides of the equation:r=−8±107
Simplify square root: Simplify the square root and round to the nearest hundredth if necessary.107 is an irrational number, so we will round it to the nearest hundredth:107≈10.34r≈−8±10.34
Find values of r: Find the two values of r.r≈−8+10.34 implies r≈2.34r≈−8−10.34 implies r≈−18.34Values of r: 2.34, −18.34
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