The functions f(x)=−2.5(x+2)2+8 and g(x)=−2.5(x+2)2+b are graphed in the xy-plane as y=f(x) and y=g(x). Let a be the y-coordinate of the vertex of function f and b be the y-coordinate of the vertex of function g(x)=−2.5(x+2)2+b0. If a is 5 less than b, then what is the value of b ?
Q. The functions f(x)=−2.5(x+2)2+8 and g(x)=−2.5(x+2)2+b are graphed in the xy-plane as y=f(x) and y=g(x). Let a be the y-coordinate of the vertex of function f and b be the y-coordinate of the vertex of function g(x)=−2.5(x+2)2+b0. If a is 5 less than b, then what is the value of b ?
Vertex form of quadratic function: The vertex form of a quadratic function is given by f(x)=a(x−h)2+k, where (h,k) is the vertex of the parabola. For the function f(x)=−2.5(x+2)2+8, the vertex (h,k) is (−2,8).
Finding the y-coordinate of the vertex: The y-coordinate of the vertex of function f is 8, which is represented by a in the problem statement.
Relationship between a and b: According to the problem, a is 5 less than b. This can be written as a=b−5.
Substituting a to find b: Substitute the value of a (which is 8) into the equation a=b−5 to find b.8=b−5
Solving for b: Add 5 to both sides of the equation to solve for b. 8+5=b 13=b
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