Respuesta :

Answer:

6a. x = 5/3

6b. x = 2

7a. x = 17

7b. y = 30, x = 3

8. 90-55 = 35

9. 180-30=150

10. 17 - 5 =12

11. opposite and corresponding angles (explanation beneath)

Step-by-step explanation:

6a. 7x-10=x+2

7x=x+10 (add 10 to both sides)

6x=10 (subtract x from both sides)

x = 5/3

6b. -3x+5(3x-1)=2x+15

12x-5=2x+15 (simplify the left side)

12x=2x+20 (add 5 to both sides)

10x=20 (subtract 2x from both sides)

x = 2

7a. (3x-10)+(2x+15) = 90

90+10= 100

100-15= 85

85/5 = 17 (as 3x + 2x = 5x)

x = 17

7b. 5y-45 = 3y +15

5y = 3y +60 (add 45 to both sides)

2y = 60 (subtract 3y from both sides)

y = 30

sub 30 for y into 3y+15: 90+15=105

straight line = 180

180-105=75

25x=75

75/25=3

x=3

8. complementary means 90º total

90-55=35 or 55+35 = 90

9. linear pair mean 180º total

180-30=150 or 30+150 =180

10. LF = 17

as LE is equal to FT, they both are equal to 5

as LE is part of LF, 17 - 5 =12

11. lm and rs are parallel

given that 9 and 12 are opposite angles, and that 12 and 8 are corresponding angles, meaning that 12 and 8 are of the same angle.

and since 12 = 8, and 12 = 9,

therefore you can prove that 8 = 9

Answer:

6. (a)

[tex]7x - 10 = x + 2[/tex]

Collect like terms

[tex]7x - x = 2 + 10[/tex]

[tex]6x = 12[/tex]

Divide both sides with 6

[tex]x = \frac{12}{6} [/tex]

[tex]x = 2[/tex]

6. (b)

[tex] - 3x + 5(3x - 1) = 2x + 15[/tex]

Expand the bracket[tex] - 3x + 15x - 5 = 2x + 15[/tex]

Collect like terms

[tex] - 3x + 15x - 2x = 5 + 15[/tex]

[tex] 10x = 20[/tex]

Divide both sides with 10

[tex]x = \frac{20}{10} [/tex]

[tex]x = 2[/tex]

7.(a)

[tex](2x + 15) + (3x - 10) = 90[/tex]

[tex]2x + 15 + 3x - 10 = 90[/tex]

[tex]5x = 90 - 15 + 10[/tex]

[tex]5x = 85[/tex]

[tex]x = 17[/tex]

7.(b)

(5y-45)° and (3y+15)° are opposite angles. Thus, they share the same value of angle.

[tex]5y - 45 = 3y + 15[/tex]

[tex]5y - 3y = 45 + 15[/tex]

[tex]2y = 60[/tex]

[tex]y = 30[/tex]

All four angles shown in the diagram will add up to a total value of 360°. So, minus 360° with the two angles we had found to find the remaining angles or x.

[tex]360 - (5(30) - 45) - (3(30) + 15) = 2(25x)[/tex]

[tex]360 - 105 - 105 = 50x[/tex]

[tex]150 = 50x[/tex]

[tex]50x = 150[/tex]

[tex]x = \frac{150}{50} [/tex]

[tex]x = 3[/tex]