1. since the equations equal each other
2x+19=x+7
-x -x
x+19=7
-19 -19
x= -12
sub into y= x+7
y= -12+7
y= -5
2. x+2y=-7
<span>x+y+23=0
i don't know what the second equation is equal to, i'll assume 0
2y=x-7
y=1/2x-7/2
sub this into x+y+23=0
x+1/2x-7/2+23=0
3/2x+39/2=0
-39/2 -39/2
3/2x= -39/2
x=-39/2 / 3/2
x= -13
sub into y=1/2x-7/2
y=1/2(-13)-7/2
y= -10
3. </span>x+5y=2
<span>x=-4y+5
</span>sub x=-4y+5 into x+5y=2
-4y+5+5y=2
y+5=2
-5 -5
y= -3
sub y =-3 into x =-4y+5
x=-4(-3)+5
x= 17
4. 3x+y=9
<span>y=-5x+9
</span>sub -5x+9 into 3x+y=9
3x+(-5x+9)=9
3x-5x+9=9
-2x+9=9
-9 -9
-2x=0
x=0
sub into y=-5x+9
y=-5(0)+9
y=9
We have to find the lengths of the diagonals KM and JL:
d ( KM ) = √ (( - a - b )² + ( 0 - c )²) = √ (( a + b )² + c² )
d ( JL ) = √ ( ( a - ( - b ) )² + ( 0 - c )²) = √ ( ( a + b )² + c² )
So the lengths of the diagonals KM and JL are congruent.
The lengths of the diagonals of the isosceles trapezoid are congruent.
Answer:
A. T > 2.539
Step-by-step explanation:
We have a hypothesis test of the mean, with unknown population standard deviation.
The hypothesis are:

From the hypothesis we can see that the test is right-tailed, so the critical value of t should be a positive value.
The degrees of freedom can be calculated as:

The significance level is 0.01, so the critical value tc should be the one that satisfies:

Looking up in a t-table, for 19 degrees of freedom, this critical value is tc=2.539.
Answer:
First ans is true but second one is not the cotrect
one
Answer: 12
Step-by-step explanation:
if there are 2 people then doing the same job then that means divide by two so 8 which is off the 28 , 8 divided by 2 is 4, then, that makes 24 , and 24 divided by 2 is 12 so the answer is 12