(3x+8)=(5x-20). The angles are vertical so it's equal. You then used the solved for x to solve (3x+8)+(5x+4y)=180 to solve for y. This is because these two angles are supplementary so they add to 180. We assume x is already known from the first equation.
Solving the first equation: 2x=28 x=14
Second equation: 3*14+8+5*14+4y=180 42+8+70+4y=180 4y=180-120 4y=60 y=15
Yes! There is enough information to solve for x. x equals 23 degrees because we know that one angle measure is 23, and that this is a right triangle so another angle measure must be 90. Since we know 2 of the angle measures, we can find the third by subtracting from 180. Seeing as the mid-line bisects this angle and creates a shared side for the 2 triangles, we know the triangles must be congruent. We could also explain this using SAA if needed. To put it short, though, there are several ways we can prove that x=23.
(3x+8)=(5x-20). The angles are vertical so it's equal. You then used the solved for x to solve (3x+8)+(5x+4y)=180 to solve for y. This is because these two angles are supplementary so they add to 180. We assume x is already known from the first equation.
Solving the first equation:
2x=28
x=14
Second equation: 3*14+8+5*14+4y=180
42+8+70+4y=180
4y=180-120
4y=60
y=15
Yes! There is enough information to solve for x. x equals 23 degrees because we know that one angle measure is 23, and that this is a right triangle so another angle measure must be 90. Since we know 2 of the angle measures, we can find the third by subtracting from 180. Seeing as the mid-line bisects this angle and creates a shared side for the 2 triangles, we know the triangles must be congruent. We could also explain this using SAA if needed. To put it short, though, there are several ways we can prove that x=23.
Solution:
1)
Statement Reason
x ║t Given
m∠16=m∠7 Given
m∠16=m∠1 Corresponding angles
m∠7=m∠1 Substitution
k║w Alternate exterior angles equal
(Property of parallel lines)
2)Part A:
Sum of angles in any triangle is 180 degrees.
m∠BAC+m∠ABC+m∠BCA= 180
Substituting the values :
4x+10+12x-6+3x+5=180
Adding like terms :
19x+9=180
19x=171
x=9.
Part B:
Substituting x value :
m∠BAC=4x+10=4(9)+10=46
m∠ABC=12x-6=12(9)-6=102
m∠BCA=3x+5=3(9)+5=32.
Part C:
m∠1=180-46=134
m∠2=180-102=78.
m∠3=180-32=148.
Part D:
Angle BAC and angle FAC are angle made on straight line and are linear .Such angles are called linear pairs.
Part E:
Angle BCE and Angle DCA are vertically opposite angles.
.
∠1 = ∠3 [vertical angles]
5x - 20 = 3x + 8
5x - 3x = 8 + 20
2x = 28
x = 14
m∠1 = 3x + 8 = 3*14 + 8 = 50°
m∠3 = m∠1 = 50°
∠1 + ∠2 = 180° [supplementary angles]
m∠2 = 180 - m∠1 = 180 - 50 = 130°
m∠4 = m∠2 = 130° [vertical angles]
(5x + 4y) = 130 [x = 14]
5*14 + 4y = 130
70 + 4y = 130
4y = 130 - 70
4y = 60
y = 60/4
y = 15
x = 14
y = 15
m∠1= 50°
m∠2= 130°
m∠3= 50°
m∠4= 130°
Because g is the centroid of the triangle abc, then ag = bg= cg
here cg = 3x+7 and bg= 6x
3x+7 = 6x
7=6x-3x
7=3x
x=7/3
for the question to be "workable", af is probably the median, with f on bc
remember the centroid cuts the median in the ratio of 2: 1, or ag: gf = 2: 1
then fg: af= 1: 3
(x+8)/(9x-6) = 1/3
9x - 6 = 3x + 24
6x = 30
x = 5