Answer:
Speed of car B is 33 km/h and speed of car A is 
Step-by-step explanation:
Let speed of car B be
km/h
Speed of car A is 12 km/h more than car B.
Therefore,
Speed of car A =
km/h
Distance = Speed × Time
Distance travelled by car A in 4 hours =
km =
km
Distance travelled by car B in 4 hours =
km
Also, cars A and B are 312km apart after 4 hours.

Speed of car B is 33 km/h and speed of car A is 
Hello,
Let's place the last digit: it must be 2 or 4 or 8 (3 possibilities)
It remainds 4 digits and the number of permutations fo 4 numbers is 4!=4*3*2*1=24
Thus there are 3*24=72 possibilities.
Answer A
If you do'nt believe run this programm
DIM n(5) AS INTEGER, i1 AS INTEGER, i2 AS INTEGER, i3 AS INTEGER, i4 AS INTEGER, i5 AS INTEGER, nb AS LONG, tot AS LONG
tot = 0
n(1) = 1
n(2) = 2
n(3) = 4
n(4) = 7
n(5) = 8
FOR i1 = 1 TO 5
FOR i2 = 1 TO 5
IF i2 <> i1 THEN
FOR i3 = 1 TO 5
IF i3 <> i2 AND i3 <> i1 THEN
FOR i4 = 1 TO 5
IF i4 <> i3 AND i4 <> i2 AND i4 <> i1 THEN
FOR i5 = 1 TO 5
IF i5 <> i4 AND i5 <> i3 AND i5 <> i2 AND i5 <> i1 THEN
nb = ((((n(i1) * 10) + n(i2)) * 10 + n(i3)) * 10 + n(i4)) * 10 + n(i5)
IF nb MOD 2 = 0 THEN
tot = tot + 1
END IF
END IF
NEXT i5
END IF
NEXT i4
END IF
NEXT i3
END IF
NEXT i2
NEXT i1
PRINT "tot="; tot
END
Answer:
Angle A is 77°
x = 3
AC = 13
Step-by-step explanation:
Angles A, B and C MUST add up to 180°. If Angle C is 26°, then the sum of A and B and 26° = 180°. In other words, A+B = 180° - 26° = 154.
Since A and B are equal, A = B = 154°/2 = 77°
Since this triangle is isosceles, sides AC and BC are equal. Thus,
7x - 8 = 3x + 4, or
4x = 12. Then x = 3.
Since AC = 7x - 8, and x = 3, AC = 7(3) - 8 = 21 - 8 = 13