Question

PLEASE HELP ASAP 9TH GRADE MATH AND I NEED HELP, 15 POINTS AND BRAINLIST HELPPPP

Answer 1

Answer:

x = 40°

Step-by-step explanation:

Given that ∠SRT ≅ ∠STR

Then ∠STR = 20

∠STR  and ∠STU are what you call supplementary angles. This means that the sum of their measurements is equal to 180° because they form a straight line.

So if:

∠STR + ∠STU = 180°

m∠STU = 4x

m∠STR = 20

Then:

4x + 20° = 180°

Now we solve for x:

$4x + 20 = 180\\\\Subtract\;20\;from\;both\;sides\;of\;the\;equation\\\\4x + 20 - 20 = 180 - 20\\4x = 160\\\\Divide\;both\;sides\;of\;the\;equation\;by\;4\\\\\dfrac{4x}{4}=\dfrac{160}{4}\\\\x = 40$

x = 40°