Let C be the amount of compost
T be the amount of topsoil
Each compost cost = $25
Cost of C compost = 25C
Each topsoil cost = $15
Cost of T topsoil = 15T
Amount of compost + amount of topsoil = 10
C + T = 10 -------> Equation 1
cost of C compost + cost of T topsoil = 180
25C + 15T = 180 --------> equation 2
Solve the first equation for C
C + T = 10
C = 10 - T
Now plug it in second equation
25C + 15T = 180
25 ( 10 - T) +15T = 180
250 - 25T + 15T = 180 (combine like terms)
250 - 10 T = 180 (Subtract 250 on both sides)
-10T = 180 - 250
-10T = -70 ( divide by -10 on both sides)
T = 7
She purchased 7 cubic yards of topsoil .
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:
x = 40°
Move variable to the left. -w= -10+ 4W
-w-4W =-10
Collect like terms
-5w=-10 divide both sides by 5