Answer:
The measure of angle x is 40°
Step-by-step explanation:
we know that
The measurement of the outer angle is the semi-difference of the arcs which comprises
see the attached figure with letters to better understand the problem
so
m∠x=(1/2)[arc AB-arc AC]
<u><em>Find the measure of arc AC</em></u>
we know that
arc AB+arc BC+arc AC=360° ----> by complete circle
substitute the given values
arc AB=200°
arc BC=40°
arc AC=?
200°+40°+arc AC=360°
240°+arc AC=360°
arc AC=360°-240°=120°
<u><em>Find the measure of angle x</em></u>
m∠x=(1/2)[200°-120°]=40°
OK to solve this, we have to solve each system presented through elimination or substitution and find which one is equivalent to that of the teacher's!
First let's solve for the teacher's:
-2x+5y=10
-3x+9y=6
Solve by substitution (I think elimination might be easier to do for this one, but I don't really remember 100% sorry!)
Isolate the x (or y) variable in the first equation
-2x+5y=10
-2x=10-5y
Substitute x into the next equation and solve for y
-3(10-5y/2)+9y=6
3*10-5y/2+9y=6
(multiply both sides by 2)
3(10-5y)+18y=12
30-15y+18y=12
30+3y=12
3y=-18
y=-6
Substitute in x
x= -10-5(-6)/2
x=-20
TEACHER'S ANSWER (-20,-6)
GOKU
x-3y=-2
-2x+5y=-7
Do the same as above
Solve for x
x-3y=-2
x=3y-2
Plug in
-2(3y-2)+5y=-7
4-6y+5y=-7
4-y=-7
-y=-11
y=11
x=(3(11)-2)
x=31
GOKU'S ANSWER (31, 11)
SELINA:
-5x+14y=16
-3x+9y=12
One last time!! :)
-5x+14y=16
-5x=16-14y
x=(16-14y)/-5
-3(-(16-14y/5)+9y=12
3*16-14y/5+9y=12
3*16-14y+45y=60
48-42y+45y=60
48+3y=60
3y=12
y=4
x=-(16-14(4))/5
x=8
SELINA'S ANSWER
(8,4)
So neither Goku or Selina got the same answer as the teacher
Answer:
0.75 was how much she paid for each postcard.
Step-by-step explanation:
6.04-3.79
=2.25
so take 2.25 divided by 3
= o.75
equations would be 6.04-3.75=b/ 3
<h2>Answer:</h2>
Number of biology textbooks sold: 257 textbooks
Number of psychology textbooks sold: 181 textbooks
<h2>Explanations:</h2>
Let the total number of biology textbook sold be "a"
Let the total number of psychology textbook sold be "b"
If a textbook store sold a combined total of 438 biology and psychology textbooks in a week, then:
a + b = 438 ................... 1
If the number of psychology textbooks sold was 76 less than the number of biology textbooks sold, then;
b = a - 76 ...................... 2
Substitute equation 2 into 1
a + (a-76) = 438
a + a - 76 = 438
2a = 438 + 76
2a = 514
a = 514/2
a = 257 biology textbooks
From equation 2;
b = a - 76
b = 257 - 76
b = 181 psychology textbooks
Number of biology textbooks sold: 257 textbooks
Number of psychology textbooks sold: 181 textbooks
