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Solve the given system of equations using the Substitution Method.
Solution: (3,4)
Graph:
We will solve the given system of equations using the Substitution Method. x^2+y^2=25 & (I) y=- 34x+ 254 & (II) The y-variable is isolated in Equation (II). This allows us to substitute its value - 34x+ 254 for y in Equation (I).
(I): y= -3/4x+25/4
(I):(a+b)^2=a^2+2ab+b^2
Calculate power and product
(I): LHS * 16=RHS* 16
(I): Add terms
(I): LHS-400=RHS-400
(I): .LHS /25.=.RHS /25.
Notice that in Equation (I) we have a quadratic equation in terms of only the x-variable. Notice that there are many ways to solve a quadratic equation. We will use Quadratic Formula. Let's determine a, b, and c. x^2-6x+9=0 ⇔ 1x^2+( - 6)x+ 9=0
Substitute values
Now consider Equation (II) in the given nonlinear system. y=-3/4x+25/4 We will substitute x=3 into the above equation to find the value for y.
We found that y=4 when x=3. Therefore, the solution of the system is (3,4).
Let's notice that Equation (I) represents a circle and Equation (II) represents a line. If you need explanations on graphing circles, please refer to this site. If you need explanations on graphing lines, please refer to this site. Let's graph them and mark the point (3,4).
Notice that the circle and the line intersect about at the point (3,4), which confirms our answer.