If isosceles triangle abc has a 130° angle at vertex b, which statement must be true?
m∠a = 15° and m∠c = 35°
m∠a + m∠b = 155°
m∠a + m∠c = 60°
m∠a = 20° and m∠c = 30°.

Step-by-step explanation:

2 angles of same length

all angles in a triangle add to 180

so

if the angles are m∠A, m∠B, m∠C, then

either m∠A=m∠B or m∠B=m∠C or m∠A=m∠C

anyway

so if we assume that vertex B is the one that has a twin then

130+130+?=180

260+?=180

?=-80

false, we can't have a negative angle measure

so 130 must be the odd one

?+?+130=180

2?+130=180

2?=50

?=25

so

m∠A=m∠C=25°

let's test the 2nd answer choice

m∠A+m∠B=25+130=155, yep

test 3rd

m∠A+m∠C=25+25=50≠60, nope

not 3rd one

so answer is 2nd statement

m∠A+ m∠B = 155°

the formula of a slope:

from a table we have

substitute:

the slope of f(x) is -1.

the graph of funcfion g(x) is a horizontal line. the slope of a horizontal line is equal 0. therefore the slope of g(x) is 0.

-1 < 0

$25

step-by-step explanation:

25 - 4.50 = 20.5

20.5 / 2 = 10.25

10.25 + 10 = 20.25

20.25 - 12.50 = 7.75

therefore the answer is $25 as shown as the first number.