Otázky k cvičnému testu z matematiky 8. třídy PARCC
1. Which of the following equations have infinitely many solutions?
1. A: A is the only one that has infinitely many solutions because when the 3 is distributed across the parentheses, the resulting equation is 6x-15=6x-15. Because each side of the equation is identical to the other side, any value of x will make a true statement, so there are infinitely many solutions.
2. John was given the following equation and asked to solve for x. 2/3 x-1=5. His solution is shown below. Circle the step where he made a mistake and then choose the answer choice that fixes it.
However, he messed up on the second step when he moved the -1 across it should have become a positive 1. That step should be 2/3 x=6.
3. Which point represents the solution to the system of linear equations graphed below?
3. C: Given the graph of a system of linear equations, the solution is the point of intersection of the two lines. In this graph, the two lines intersect at (-2,-1).
4. Solve the system of linear equations.
4. A: 3x-2(2x+5)=-10 Substitute the expression for y into the other equation 3x-4x-10=-10 Distribute the -2 across the parentheses -x-10=-10 Combine like terms -x=0 Add 10 to both sides x=0 Divide by -1 y=2(0)+5=5 Substitute the value of x into the original equation and simplify. (0,5) Write your final answer as an ordered pair (x,y)
5. Jonas walks at half the pace of his jogging speed. Draw a graph that shows how far he has gone after x minutes.
5. If Jonas walks at half the pace he jogs then he will only cover half on the distance when walking. The line is shown below.