System by elimination

2x - y = -3
-2x - 8y = 12

x= -2 y= -1

Step-by-step explanation:

stack the 2 equations on top of each other and add them together

the 2x and -2x cancel out and you are left with -9y=9

this gives you y= -1

you plug the y value into one of the equations:

2x - (-1) = -3

2x+1 = -3

2x= -4

x= -2

1 number

if we use a graphing calculator, there is only one such number that satisfies the conclusion of the mean value theorem, that is, a number such that

where the right-hand side is the average rate of change of f on the interval [0.5,0.75], which is the slope of the secant line.

in the attached graph, the black line is the secant line which has its slope as the average rate of change of f on [0.5,0.75], while the orange line is the only tangent line to the graph of f in the interval that satisfies the mvt conclusion.

investment b is an ordinary annuity with $3,909.64 in the account after one year.

step-by-step explanation: